I recently slotted gnu-classpath-inetlib because gnu-javamail does not work with the 1.1 version. So on amd64 the gnu-javamail was/is broken. So please test the older gnu-classpath-inetlib and add the keywords to it and gnu-javamail.
gnu-classpath-inetlib-1.0-r1 seems to work for me on amd64.
Fixed in CVS.