SPSiteDataQuery fails if field of type UserMulti is specified in ViewFields

I`m trying to query all task lists. I have modified default Task content type to allow multiple choices for Assigned To field (Internal name - AssignedTo).

My SPSiteDataQuery fails if I specify <FieldRef Name='AssignedTo' /> (Returns no results) If I add Nullable='TRUE' then results are returned but AssignedTo field ends up being null for all records. If i'll add Type='UserMulti', that won't help.

Looks like a very nasty bug. Is there a workaround? (Well, besides looping all task li开发者_高级运维sts and querying...)

Thankyou.

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We faced the same exact issue two months back, I came across this thread , after which I used the Nullable='TRUE' Type='UserMulti' Still then we were not able get it working. And my manager sat with MS support to just find out that Installing the MOSS 2007 SP2 solved the issue with out a code change. You can try out SP2 in case if you haven't already.