stored proc parameter type mismatch

When my classic asp calls stored proc, parameter types are not specified. This is fine most of time, but if this funcionality is highly used, applications gets error sometimes.

Error:
sql native client procedure or function [sp name] expects parameter [parameter name], which was not supplied.

This is not a replicatable issue, but happens from time to time.
I guess the problem is SQL server guesses parameter type every time, and there is small chance it guesses incorrectly.

I can fix this issue by specifying parameter types, but there are hundreds of places to be fixed.

Is there a better way to fix this? Thanks you.