No SOAP?

Well it's a funny thing; and I hope someone with network smarts is feeling charitable enough to provide some guidance to an end-user numbskull like me.
The Problem:
My stock quote applescript (called from the menubar) has suddenly stopped working, returning the error:

http://services.xmethods.net:80/soap got an error: AppleEvent timed out.

Not only that, but I notice that certain shareware apps' (for example Transmit) "Check for Update" functionality is also broken.

What I know:
This occurred after updating to 10.3.9. Yesterday I combo-updated from 10.3.6. Prior to the update, all was fine. At that time, I also installed: "AirPort Software" (4.1); "iCal" (1.5.5); "iSight Update" (1.0.3); "Security Update 2005-002" (2.0.0); "iPod Updater 2005-03-23" ((null)); "Security Update 2005-004" (1.0); "Java Update for Mac OS X v10.3.9" (1.0).
After the update, a permissions repair returned, in addition to a raft of "using special permissions" notices,

Permissions differ on ./private/etc/slpsa.conf, should be -rwxr-xr-x , they are -rw-r--r--
Owner and group corrected on ./private/etc/slpsa.conf
Permissions corrected on ./private/etc/slpsa.conf

I am running a stock firewall; and turning it off made no difference. Running fsck in single-user mode shows no problems.
I have no problems with browsing and mail; and in fact notice no problems at all aside from the above. In fact, I at first thought it was a problem external to my machine; but I've seen no mention of it here or elsewhere and so now conclude otherwise.

So the truth is - I have no idea how to go about troubleshooting this and don't really even understand the nature of the problem in the first place.

Thanks for any advice.