upgrade to version 3.1.1

I have tried using the automoatic upgrade to get to version 3.1.1
I have been doing this since the feature was added and have not changed my host.
I keep getting this error message
Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 3096504 bytes) in /home/stefanra/public_html/blog/wp-includes/class-http.php on line 1426

Any ideas I dont fancy doing a manual upgrade