The check for JAVAC is in the wrong order - it will select a third party JAVAC over GCJ (the latter may not even work).
Index: frysk-imports/common/ChangeLog 2005-11-29 Andrew Cagney <cagney@redhat.com> * acinclude.m4 (AC_CHECK_PROGS([JAVAC]): Check for javac last..
fixed by change