Crystal Reports Pass parameter values from Main to Sub report

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     Hello All, 

Hope all is well. I am a newbie to Crystal reports. I am kinda stuck here...I am trying to Link parameter of a Main to the Parameter of the Sub Report. But for some reasons, I dont see parameters of the Sub report in the drop down of linking option , when I try to link parameter of the main report to sub reports.

So I tried to create a formula in the sub report, which were nothing but 
=(Parameter of Sub Report), now formual of child report do show up in drop down list when trying to link main report parameter....but the problem is when I link main report parameter to the Formula , then formula is actually evaluated at the report level....for example country='us' at report level as oppose to it being in SQL level.

I am sure missing something obvious, appreciate your help on this.

Thanks in advance,

Sam

Edited by samshaw - 15 Apr 2008 at 8:51am