--- /usr/lib/portage/pym/portage.py.orig	2007-01-15 19:56:09.000000000 +0100
+++ /usr/lib/portage/pym/portage.py.orig	2007-01-15 22:19:31.000000000 +0100
@@ -5905,7 +5905,6 @@ 
 			mysymlinks = filter(os.path.islink, listdir(srcroot, recursive=1, filesonly=0, followSymlinks=False))
 			myfilelist.extend(mysymlinks)
 
-			stopmerge=False
 			starttime=time.time()
 			i=0
 
@@ -5924,6 +5923,7 @@ 
 							vartree=self.vartree))
 
 			print green("*")+" checking "+str(len(myfilelist))+" files for package collisions"
+			collidingfiles = []
 			for f in myfilelist:
 				nocheck = False
 				# listdir isn't intelligent enough to exclude symlinked dirs,
@@ -5946,18 +5946,79 @@ 
 						break
 				if not isowned:
 					print "existing file "+f+" is not owned by this package"
-					stopmerge=True
+					collidingfiles.append(f)
 			print green("*")+" spent "+str(time.time()-starttime)+" seconds checking for file collisions"
-			if stopmerge:
+
+			stopmerge = False
+			# The three if-clauses could technically be combined and nested,
+			# However, practically the indentation depth gets to deep.
+			if collidingfiles:
+				# Check for qlist from app-portage/portage-utils
+				# FIXME: Currently only standard location /usr/bin/qlist supported
+				hasqfile = os.access('/usr/bin/qfile', os.X_OK)
+				print
 				print red("*")+" This package is blocked because it wants to overwrite"
-				print red("*")+" files belonging to other packages (see messages above)."
+				print red("*")+" files possibly belonging to other packages (see messages above)."
 				print red("*")+" If you have no clue what this is all about report it "
-				print red("*")+" as a bug for this package on http://bugs.gentoo.org"
+				print red("*")+" as a bug for this package on http://bugs.gentoo.org."
+				if not "collision-protect-ask" in self.settings.features:
+					stopmerge = True
+					print
+					print red("*")+" To get some interactivity add collision-protect-ask"
+					print red("*")+" to your FEATURES list."
+				if not hasqfile:
+					print
+					print red("*")+" You might want to install app-portage/portage-utils"
+					print red("*")+" to get the qfile utility, it finds file owners and"
+					print red("*")+" helps to investigate the problem."
+
+			if collidingfiles and "collision-protect-ask" in self.settings.features:
+				# User asks for interactivity
+				answered = False
+				while not answered:
+					# FIXME: This should not clutter the terminal buffer,
+					# but in case of not_answered be overwritten."
+					print
+					print green("*")+" You enabled the collision-protect-ask feature."
+					print green("*")+" What do you want to do?"
+					print green("*")+"  1. Overwrite those files and continue the merge,"
+					print green("*")+"      I checked that no package is owning them"
+					print green("*")+"      (using e.g. qfile from app-portage/portage-utils)"
+					print green("*")+"      or I know what I am doing!"
+					print   red("*")+"      Anyway, I will file a bug as asked for above."
+					print green("*")+"  2. Please find out, who is owning these files, I have"
+					print green("*")+"      qfile from app-portage/portage-utils installed."
+					print green("*")+"  3. Abort merge! (the same, as if you would not have"
+					print green("*")+"      set the collision-protect-ask feature)"
+					print green("*")+" (1/2/3)? ",
+					a = sys.stdin.readline().rstrip()
+					if a == '1':
+						# continue as if without collision
+						answered = True
+					elif a == '2':
+						# run qlist
+						if not hasqfile:
+							# FIXME: suggestion to user needs to be given
+							print
+							print red("*")+" NO, you don't have qfile installed."
+						else:
+							print
+							print green("*")+"Running qfile for colliding files:"
+							for f in collidingfiles:
+								print f+':'
+								res = os.system('/usr/bin/qfile '+f)
+								if res != 0:
+									print "  Not owned by any package."
+					elif a == '3':
+						stopmerge = True
+						answered = True
+
+			if stopmerge:
 				print
 				print red("package "+self.cat+"/"+self.pkg+" NOT merged")
 				print
 				# Why is the package already merged here db-wise? Shouldn't be the case
-				# only unmerge if it ia new package and has no contents
+				# only unmerge if it is a new package and has no contents
 				if not self.getcontents():
 					self.unmerge(ldpath_mtimes=prev_mtimes)
 					self.delete()