ActiveSync 4.2 and IMAP email

I use IMAP4 email vs. ActiveSync for email. For some reason after upgrading to 4.2 I find I can not send email using the passthrough mode in ActiveSync. I can send email if I connect using either WiFi or and Ethernet card to get to the network. This only started after I upgraded to ActiveSync 4.2 Has anyone else seen this problem or found a solution other then only sending using WiFi or and ehternet card?
Thanks

[JordanChris]

Does this solve things??

ACTIVE SYNC V4.2 and PASS-THRU

ActiveSync version 4.2 made a change to how it interacts with the Windows networking stack to use Layered Service Providers (LSPs) on outgoing Desktop-Pass-Through connections. This allows for improved compatibility in environments where connections to the internet must be passed through these LSPs (ISA Proxy is one such example). Unfortunately, it appears this change has caused some issues for a small segment of users who have LSPs that interfere with ActiveSync communication.
http://pdaphonehome.com/forums/552203-post22.html

I tried that fix and it did not resolve the problem.