package variable to DataFlow query paramter

Hi All,

I have written Procedure

example

create proc (@var varchar(20))

begin

......

.....

end

This procedure i want run from data flow task in ssis,

in the SQL command option i wrote as follows

execute proc <here i need to pass variable,already defined in package>

i tried to give "?" and i map the variable in the paramters option,

but it gives an error as follows

[OLE DB Source [17]] Error: The SQL command requires a parameter named "@tagname", which is not found in the parameter mapping.

Any one have aware of this problem, Please help me
thanks in advance

chinnikrishna