mod() gives an error sqlPrepareWithOptions

[niloco]

Hi all !

I'm trying to use the alternating rows with running-count(). Therefore i need to use the mod function in an expression.
But while validating/running the report, i get an error:
sqlPrepareWithOptions' status-69'.
After some testing, we narrowed the errorscript to:

mod(2, 2)

We use Cognos 8.4
And i'm a beginner user.

Does the mod function somehow depend on database functions? Do we have to configure Cognos with special options ?
Do we have to (over)cast integers?

Regards,
Niloco