How does WF hosted as WCF in IIS 6 resume after delay?

Does a WF hosted as WCF (.NET 3.5) in IIS 6 resume after a delay activity when persisted to SqlWorkflowPersistenceService ? And if so, which kind of thread is being used (one from the ASP.NET worke开发者_Go百科r threads or a background thread from IIS ?)

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.NET code never uses "a thread from IIS 6". It's always an ASP.NET worker thread.

In IIS 7 the two are the same.