diff -urN unionfs-1.1.3.old/copyup.c unionfs-1.1.3.new/copyup.c
--- unionfs-1.1.3.old/copyup.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/copyup.c	2006-04-03 22:35:26.413786991 -0300
@@ -64,7 +64,11 @@
 	name_list_orig = name_list;
 	while (*name_list) {
 		ssize_t size;
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&old_hidden_dentry->d_inode->i_mutex);
+#else
 		down(&old_hidden_dentry->d_inode->i_sem);
+#endif
 		err = security_inode_getxattr(old_hidden_dentry, name_list);
 		if (err)
 			size = err;
@@ -73,7 +77,11 @@
 			    old_hidden_dentry->d_inode->i_op->
 			    getxattr(old_hidden_dentry, name_list, attr_value,
 				     XATTR_SIZE_MAX);
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&old_hidden_dentry->d_inode->i_mutex);
+#else
 		up(&old_hidden_dentry->d_inode->i_sem);
+#endif		
 		if (size < 0) {
 			err = size;
 			goto out;
@@ -84,7 +92,11 @@
 			goto out;
 		}
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&new_hidden_dentry->d_inode->i_mutex);
+#else
 		down(&new_hidden_dentry->d_inode->i_sem);
+#endif
 
 		err =
 		    security_inode_setxattr(old_hidden_dentry, name_list,
@@ -101,7 +113,11 @@
 							     attr_value, size,
 							     0);
 		}
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&new_hidden_dentry->d_inode->i_mutex);
+#else
 		up(&new_hidden_dentry->d_inode->i_sem);
+#endif
 
 		if (err < 0)
 			goto out;
diff -urN unionfs-1.1.3.old/dentry.c unionfs-1.1.3.new/dentry.c
--- unionfs-1.1.3.old/dentry.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/dentry.c	2006-04-03 22:35:36.633885836 -0300
@@ -108,7 +108,12 @@
 		interpose_flag = INTERPOSE_REVAL_NEG;
 		if (positive) {
 			interpose_flag = INTERPOSE_REVAL;
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+			mutex_lock(&dentry->d_inode->i_mutex);
+#else
 			down(&dentry->d_inode->i_sem);
+#endif
+
 			bstart = ibstart(dentry->d_inode);
 			bend = ibend(dentry->d_inode);
 			if (bstart >= 0) {
@@ -126,7 +131,11 @@
 			itohi_ptr(dentry->d_inode) = NULL;
 			ibstart(dentry->d_inode) = -1;
 			ibend(dentry->d_inode) = -1;
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+			mutex_unlock(&dentry->d_inode->i_mutex);
+#else
 			up(&dentry->d_inode->i_sem);
+#endif
 		}
 
 		result = unionfs_lookup_backend(dentry, interpose_flag);
diff -urN unionfs-1.1.3.old/dirhelper.c unionfs-1.1.3.new/dirhelper.c
--- unionfs-1.1.3.old/dirhelper.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/dirhelper.c	2006-04-03 22:35:45.579217856 -0300
@@ -78,11 +78,19 @@
 				continue;
 			}
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+			mutex_lock(&hidden_dir_dentry->d_inode->i_mutex);
+#else
 			down(&hidden_dir_dentry->d_inode->i_sem);
+#endif
 			err =
 			    vfs_unlink(hidden_dir_dentry->d_inode,
 				       hidden_dentry);
-			up(&hidden_dir_dentry->d_inode->i_sem);
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+			mutex_unlock(&hidden_dir_dentry->d_inode->i_mutex);
+#else
+			down(&hidden_dir_dentry->d_inode->i_sem);
+#endif
 			DPUT(hidden_dentry);
 
 			if (err && !IS_COPYUP_ERR(err))
diff -urN unionfs-1.1.3.old/file.c unionfs-1.1.3.new/file.c
--- unionfs-1.1.3.old/file.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/file.c	2006-04-03 22:42:17.319560146 -0300
@@ -264,10 +264,18 @@
 	if (!hidden_file->f_op || !hidden_file->f_op->fsync)
 		goto out;
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+	mutex_lock(&hidden_file->f_dentry->d_inode->i_mutex);
+#else
 	down(&hidden_file->f_dentry->d_inode->i_sem);
+#endif
 	err = hidden_file->f_op->fsync(hidden_file, hidden_file->f_dentry,
 				       datasync);
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+	mutex_unlock(&hidden_file->f_dentry->d_inode->i_mutex);
+#else
 	up(&hidden_file->f_dentry->d_inode->i_sem);
+#endif
 
       out:
 	print_exit_status(err);
diff -urN unionfs-1.1.3.old/inode.c unionfs-1.1.3.new/inode.c
--- unionfs-1.1.3.old/inode.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/inode.c	2006-04-03 22:42:17.346555567 -0300
@@ -81,7 +81,11 @@
 		struct dentry *hidden_dir_dentry;
 		struct iattr newattrs;
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&whiteout_dentry->d_inode->i_mutex);
+#else
 		down(&whiteout_dentry->d_inode->i_sem);
+#endif
 		newattrs.ia_valid = ATTR_CTIME | ATTR_MODE | ATTR_ATIME
 		    | ATTR_MTIME | ATTR_UID | ATTR_GID | ATTR_FORCE
 		    | ATTR_KILL_SUID | ATTR_KILL_SGID;
@@ -97,7 +101,11 @@
 
 		err = notify_change(whiteout_dentry, &newattrs);
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&whiteout_dentry->d_inode->i_mutex);
+#else
 		up(&whiteout_dentry->d_inode->i_sem);
+#endif
 
 		if (err)
 			printk(KERN_WARNING
@@ -594,10 +602,20 @@
 				err = PTR_ERR(whiteout_dentry);
 				goto out;
 			}
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+			mutex_lock(&hidden_dentry->d_inode->i_mutex);
+#else
 			down(&hidden_dentry->d_inode->i_sem);
+#endif
+
 			err = vfs_create(hidden_dentry->d_inode,
 					 whiteout_dentry, 0600, NULL);
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+			mutex_unlock(&hidden_dentry->d_inode->i_mutex);
+#else
 			up(&hidden_dentry->d_inode->i_sem);
+#endif
+
 			DPUT(whiteout_dentry);
 
 			if (err) {
diff -urN unionfs-1.1.3.old/main.c unionfs-1.1.3.new/main.c
--- unionfs-1.1.3.old/main.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/main.c	2006-04-03 22:42:17.365552345 -0300
@@ -103,7 +103,12 @@
 		}
 	}
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+	mutex_lock(&inode->i_mutex);
+#else
 	down(&inode->i_sem);
+#endif
+
 	if (atomic_read(&inode->i_count) > 1)
 		goto skip;
 
@@ -172,7 +177,11 @@
 
 	fist_print_dentry("Leaving unionfs_interpose", dentry);
 	fist_print_inode("Leaving unionfs_interpose", inode);
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+	mutex_unlock(&inode->i_mutex);
+#else
 	up(&inode->i_sem);
+#endif
 
       out:
 	print_exit_status(err);
diff -urN unionfs-1.1.3.old/unionfs.h unionfs-1.1.3.new/unionfs.h
--- unionfs-1.1.3.old/unionfs.h	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/unionfs.h	2006-04-03 22:42:17.385548953 -0300
@@ -776,13 +776,22 @@
 {
 	struct dentry *dir = DGET(dentry->d_parent);
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+	mutex_lock(&dir->d_inode->i_mutex);
+#else
 	down(&dir->d_inode->i_sem);
+#endif
+
 	return dir;
 }
 
 static inline void unlock_dir(struct dentry *dir)
 {
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+	mutex_unlock(&dir->d_inode->i_mutex);
+#else
 	up(&dir->d_inode->i_sem);
+#endif
 	DPUT(dir);
 }
 
diff -urN unionfs-1.1.3.old/xattr.c unionfs-1.1.3.new/xattr.c
--- unionfs-1.1.3.old/xattr.c	2006-02-20 19:47:06.000000000 -0300
+++ unionfs-1.1.3.new/xattr.c	2006-04-03 22:42:17.394547426 -0300
@@ -77,14 +77,22 @@
 
 		encoded_value = (char *)value;
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&hidden_dentry->d_inode->i_mutex);
+#else
 		down(&hidden_dentry->d_inode->i_sem);
+#endif
 		/* lock_kernel() already done by caller. */
 		err =
 		    hidden_dentry->d_inode->i_op->getxattr(hidden_dentry,
 							   encoded_name,
 							   encoded_value, size);
 		/* unlock_kernel() will be done by caller. */
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&hidden_dentry->d_inode->i_mutex);
+#else
 		up(&hidden_dentry->d_inode->i_sem);
+#endif
 
 	}
 
@@ -112,12 +120,20 @@
 		    name, (unsigned long)size, flags);
 
 	if (hidden_dentry->d_inode->i_op->setxattr) {
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&hidden_dentry->d_inode->i_mutex);
+#else
 		down(&hidden_dentry->d_inode->i_sem);
+#endif
 		/* lock_kernel() already done by caller. */
 		err = hidden_dentry->d_inode->i_op->
 		    setxattr(hidden_dentry, name, value, size, flags);
 		/* unlock_kernel() will be done by caller. */
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&hidden_dentry->d_inode->i_mutex);
+#else
 		up(&hidden_dentry->d_inode->i_sem);
+#endif
 	}
 
 	unlock_dentry(dentry);
@@ -143,13 +159,21 @@
 	if (hidden_dentry->d_inode->i_op->removexattr) {
 		encoded_name = (char *)name;
 
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&hidden_dentry->d_inode->i_mutex);
+#else
 		down(&hidden_dentry->d_inode->i_sem);
+#endif
 		/* lock_kernel() already done by caller. */
 		err =
 		    hidden_dentry->d_inode->i_op->removexattr(hidden_dentry,
 							      encoded_name);
 		/* unlock_kernel() will be done by caller. */
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&hidden_dentry->d_inode->i_mutex);
+#else
 		up(&hidden_dentry->d_inode->i_sem);
+#endif
 	}
 
 	unlock_dentry(dentry);
@@ -173,13 +197,21 @@
 
 	if (hidden_dentry->d_inode->i_op->listxattr) {
 		encoded_list = list;
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_lock(&hidden_dentry->d_inode->i_mutex);
+#else
 		down(&hidden_dentry->d_inode->i_sem);
+#endif
 		/* lock_kernel() already done by caller. */
 		err =
 		    hidden_dentry->d_inode->i_op->listxattr(hidden_dentry,
 							    encoded_list, size);
 		/* unlock_kernel() will be done by caller. */
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
+		mutex_unlock(&hidden_dentry->d_inode->i_mutex);
+#else
 		up(&hidden_dentry->d_inode->i_sem);
+#endif
 	}
 
 	unlock_dentry(dentry);