Execute SQL Task - passing parameter problem

[Raghav1981]

I have an Execute SQL Task


DECLARE
@SERVER VARCHAR(8000)

SET @SERVER = ?

SELECT COUNT(*) FROM MASTER.DBO.SYSSERVERS WHERE SRVNAME = @SERVER

In the Execute SQL Task parameter mapping, I create an INPUT param,
set my value to a variable and set parameter name to 0.

When Executing the query i get an error "Syntax error, permission violation,
or other nonspecific error"

where as if remove the declared variable and tried with direct query like below

SELECT COUNT(*) FROM MASTER.DBO.SYSSERVERS WHERE SRVNAME = ?

it works exactly fine.

any idea why its not working with declared variable.