An error occurred while retrieving workflow task details

I am trying to create a basic workflow in sharepoint services 3 sp1

As a test, it uses infopath travel form which is embedded into the SPS3 Travel document library as a template so when the user clicks "new" it automatically opens up a blank infopath travel form.

I've created a new 'workflow' column with the following three-state workflow:

Active, Ready for Review, and Complete

The manager receives the form for review but when they click Edit this task to mark the task complete, Outlook returns:

"An error occurred while retrieving workflow task details. This could be caused by not having connectivity to the server or because the task no longer exists. it this error persists, contact your system administrator"

Wireshark tells me workflow.aspx does not exist. I suspect this is because the workflow library ships only in Sharepoint Server 2007

How does one get workflow in sharepoint services 3 working if this is the case???

Thanks!!