Can you use '-v' with pg_dumpall and output to the log file? That might help. Likely something is not right with the individual pg_dump processes that work inside the pg_dumpall.
Payal Singh, OmniTi Computer Consulting Inc. Junior Database Architect, Phone: 240.646.0770 x 253
I built a new server running centos 6.4 and postgresql 8.4. I backed up all the databases from the old server running fedora and postgresql 8.1 using this script.