How to get first day of current fiscal year in SSRS expression?

Hi all,

I know how to do this in tsql, but the ssrs dateadd function is different. Our fiscal year is 12/1 - 11/30. How do I get the first day of the current fiscal year in an ssrs expression (will be used as a parameter). So executed today, the result should be 12/1/2011 (or however datetimes get naturally formatted).

Thanks much,

sff