[imp] imp with courrier imap is too slow

[Xrisroforos Silligardos]

I have installed the following:
 
a.. Horde: 2.2.7
a.. IMP: 3.2.6 
the problem is that inbox is too slow.It took me 5 minutes in order to see 1200 emails!
I installed imap proxy and php accelerator to improve the situation but the difference was not obvious.
Are there any suggestions about this problem?I need your help!
Thank you,
Christofer.