Cannot build RHEL5/F18 packages on Fedora 18

[Michael Cronenworth]

I had to build my first RHEL5 and F18 packages today after upgrading my
Koji server from Fedora 17 to 18. I cannot build RHEL5 or F18 packages,
but RHEL6 packages compile fine. All packages built successfully under
Fedora 17.

RHEL5 root.log:
[snip]

DEBUG util.py:264:  error reading information on service rdisc: Cannot allocate memory
DEBUG util.py:264:  warning: %post(iputils-20020927-46.el5.i386) scriptlet failed, exit status 1
DEBUG util.py:264:  Non-fatal POSTIN scriptlet failure in rpm package iputils-20020927-46.el5.i386
DEBUG util.py:264:  error reading information on service iscsid: Cannot allocate memory
DEBUG util.py:264:  error reading information on service iscsi: Cannot allocate memory
DEBUG util.py:264:  warning: %post(iscsi-initiator-utils-6.2.0.872-6.el5.i386) scriptlet failed, exit status 1
DEBUG util.py:264:  Non-fatal POSTIN scriptlet failure in rpm package iscsi-initiator-utils-6.2.0.872-6.el5.i386

RHEL5 build.log:
[snip]
gcc: error trying to exec 'cc1': execvp: No such file or directory

F18 build.log:
[snip]
collect2: fatal error: cannot find 'ld'

Is F18's mock broken?

Michael