Site5 - weird things happen with Drupal 6.6?

I have one Site5 account that drives me crazy.

I have Drupal 6.6 installed and 100 web sites using the core Drupal. All work fine until this week.

Upgraded to Drupal 6.6 this week and now things are weird.

I'm doing a simple test - click "Administer" then "Modules".

I have about 100 drupal modules installed that all work fine.

However, some of the sites will load the Modules page in 2 seconds and many time out after 60 seconds. Some of these sites are exactly the same - one loads in 2 seconds the other is stuck in some kind of loop.

I've worked with the Site5 folks and they have no idea what the problem is. They had me run WinMTR and there is NO communication problem at all.

I have no idea what the problem is.

I've ground to a halt and if I can't figure this out must abandon Drupal and go back to TikiWiki.

Anyone have any ideas?

by the way welcome to http://www.voguecatch.com