How to select a particular InfoProvider based on variable in BEx Query

Hi,

The MultiProvider is built on InfoProvider 1, 2 & 3 and a variable on 0CALMONTH. If the 0CALMONTH is CURRENT month then it should get the data from InfoProvider 1 & 3 only, otherwise it should be from InfoProvider 2 &3. How could I accomplish it, please?

Thanks,

Venkat.