[imp] Problem importing message with 20mb attachment.

[Sebastian]

I am trying to import messages into a fresh installation of horde+imp in 
wamp, but i receive this error on the debug log:

Dec 30 21:46:17 HORDE [debug] [horde] Max memory usage: 5767168 bytes 
[pid 280 on line 340 of "C:\wamp\www\horde\lib\Horde\Registry.php"]
Dec 30 21:46:23 HORDE [debug] [imp] Max memory usage: 7340032 bytes [pid 
280 on line 340 of "C:\wamp\www\horde\lib\Horde\Registry.php"]
Dec 30 21:46:29 HORDE [debug] [imp] Max memory usage: 8912896 bytes [pid 
280 on line 340 of "C:\wamp\www\horde\lib\Horde\Registry.php"]
Dec 30 21:46:54 HORDE [debug] [imp] Max memory usage: 9699328 bytes [pid 
280 on line 340 of "C:\wamp\www\horde\lib\Horde\Registry.php"]
Dec 30 21:47:01 HORDE [debug] [horde] Max memory usage: 6553600 bytes 
[pid 280 on line 340 of "C:\wamp\www\horde\lib\Horde\Registry.php"]
Dec 30 21:47:41 HORDE [debug] [horde] Max memory usage: 8650752 bytes 
[pid 280 on line 340 of "C:\wamp\www\horde\lib\Horde\Registry.php"]


I've set the memory limit in php.ini to 512mb, what other setting should 
I change?

My .mbox file is 27mb, and its only one message with attachment so I 
cant split it more than I already did.

Thanks.