Notes/Domino 6 and 7 Forum : Is Lotus Notes SCHIZOPHRENIC?

We experienced very strange problem and nobody of our developer team has explanation for this simple problem:

We have action "Process Document", which changes the value of the field Processed from empty string "" to "OK":

doc.Processed = "OK"
Call doc.Save (True,True)

We have View to see all documents, both processed ("OK") and unprocessed ("").And now what is strange:

If we later run any agent on any recently 'processed' document using coll = db.UnproccessedDocuments and set doc = coll.GetFirstDocument, command doc.Processed(0) returns always empty string and not "OK"!

BUT:
If we access the very same document in same view with Set doc = session.DocumentContext, the command doc.Processed(0) always returns expected value "OK".

In Document Properties is the value in Processed field also "OK".

We also found, that if we restart LN Client (not only database, but entire Lotus Notes!), the agent returns correct value "OK"!

This issue was tested with same results on all R6 clients and servers (6.0 - 6.0.3.)

Question: Can somebody explain, why the agent returns on 'processed' documents empty string and not "OK" as expected? And why it works after LN client restart?

Thanks for any help!