Imp Speed Help

[Lomax P Boyd]

I've searched the list and found a few threads on large mailboxes and
imp. Some appear to have no problem with them others do (like us). In
our test environment with no other users 600 messages takes approx 45
seconds to download with IMP verses 12-14secs with messenger. 
Our Config:

apache 139 (Sun x1e 1gig memory)
php 405 (compiled with uw-imap 4.7c libraries)
Horde 126
Imp 226
Solaris 8
Netscape Enterprise Imap server 3.6 (Test box Sun Ultra 10 256kmemory)

Read a tip about chmod +t on the mailboxes to put them in memory, but
that didn't seem to improve things, also followed a thread about imap
caching which appears not to be a real fix. The problem seems to be with
the IMAP server itself when loaded the inbox header information. Is it
possible that the uw-imap libraries are causing a problem with
netscape?  Would moving IMP local to the machine help? (don't believe it
will since it still needs to use 143 to talk the imap server). 

If more info is desired we can supply it, any help or suggestions will
be appreciated...