One page checkout Vs 5 page checkout calculates amount differently?

[indus]

Hi

 

I have a payment module integrated into my site, but it always gives me an invalid amount error on using the one page checkout process, while the 5 page checkout works absoulutely fine.

 

The module creators are looking into the issue, but i would like to know if there is a difference in teh way the final amount if passed to cart in one page checkout vs 5 page checkout.

 

Where should i be looking to trouble shoot this.

 

Common sense says taht both should pass total amount the same way but it seems that is not true.

 

 

 

indus