Problems upgrading to 7.4

I have a 7.1.3 instance of postgres running on one machine and want to move the database from that machine to a new
machinerunning 7.4.1.  We've installed 7.4.1 and I have successfully run pg_dump on the 7.1.3 machine and transferred
thefile over.  However when I run pg_dump to restore the data, one table with approx 5.5 million records gives me 

ERROR:  invalid memory alloc request size 1073741824

For various reasons, I do a dump/restore on the 7.1.3 machine nightly and this gives no problems.

The 7.1.3 machine is running Red Hat Linux 6.2
The 7.4.1 machine is running Red Hat Linux v9

Has anyone any idea as to how I can get round this problem?  Obviously a dump of INSERT commands is not going to be
practicalas I'll probably still be here at Christmas waiting for the restore! 

Many thanks
Hilary

Hilary Forbes
The DMR Information and Technology Group  (www.dmr.co.uk)
Direct tel 01689 889950 Fax 01689 860330
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