[openbox] How to switch off 'roll-up' via mouse-wheel

[meino.cramer at gmx.de]

Hi,

 there is a feature in openbox, which I want to disable, since --
 while working with blender -- I often touch the window title (and
 beyond) accidentally while zooming the window contents via the 
 mouse wheel and ZAP! I either will be beamed to a totally different
 workspace or the blender window will be rolled up.

 Where I have to change what to disable this feature?

 Thank you very much for your help in advance! :)
 Best regards,
 mcc