Can't VACUUM or dump! ERROR nodeRead

I created a couple of VIEWS and then dropped them, but after
 dropping them, I got the error message:

 ERROR: nodeRead: Bad Type 0

 Since then, I can't vacuum or dump. Any time I try, the process
 stops with the same error message.

 I can apparently access the data fine, but since I can't vacuum
 performance has been degrading rapidly (I do major bulk deletes
 and inserts every night). Since I can't

 I am running Linux RedHat 5.1 (Kernel 2.1.113) and PostgreSQL
 6.3.2 on a Pentium II dual-processor SMP machine.

 Any suggestions?

 thornton