MarketPress requiring an absurd amount of memory

Some information:

Memory use
total used free shared buffers cached
Mem: 995 406 589 0 24 168
-/+ buffers/cache: 212 782
Swap: 2998 0 2998

As you can see, I have over 500MB of free RAM in addition to swap space.

My relevant PHP settings for this site are as follows


Any attempt to visit the administration page results in the following error:

Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 292606 bytes) in /home/paper/public_html/wp-includes/functions.php on line 251

Is this usual behavour? It’s upsetting that I can’t even use marketpress on a VPS, let alone bothering to try and use it on my clients shared hosting.