Hi, because I had a similar problem (I tried to rebuild kdebase) as described in the SL-Users mail list topic "Any hint on 'builtin `mkstemp' requested by frozen file is not supported'?" Is there a reason why m4-1.4.8-1 from SL is only in the SRPMS repository, but not in the RPM repositories? ftp://ftp.scientificlinux.org/linux/scientific/50/SRPMS/SL/m4-1.4.8-1.src.rpm ftp://ftp.scientificlinux.org/linux/scientific/50/i386/SL/m4-1.4.5-3.el5.1.i386.rpm I know RHEL5 has only m4-1.4.5-3.el5.1. Urs