In a method for improving cold starting of a catalytically active component in gas generation systems for a mobile fuel cell system, a temporary store is arranged directly in the starting-material gas stream. During cold starting, the temporary store stores gaseous constituents from the gaseous starting material, which constituents cause problems when starting, and releases such constituents (which have been stored during the cold-start phase) again as a result of the heating which takes place as operation of the system continues.