Version history for 2.5.0.37 contains this entry:
"Bug with string output parameters fixed"
This refers to random access violations that could occur when using output parameters of type string. The random access violations are indeed gone in 2.5.0.37, but there's still a problem with these parameters:
If the SQL statement returns "null" for the parameter, the parameter does not have the value "null" but has an empty string. (Property IsNull of the Parameter is false)