[opencms-dev] change resource type for "Create new index file in new folder"

[G.R.]

Hello list,

when creating a new folder the user is prompt, to also create a new 
index ("Create new index file in new folder"). It then creates a page 
based on resource type "Page". Instead I want to use one specific 
structured content.

Does anybody know how to realize / configure that.
Thank's in advance for your help.

bye, Georg