list template doesn't appear in sub sites

hello ,

I created a list template from document library in a sub site , but when I try to create any new document library in any sub site using the saved template >  I cannot see the template in the libraries list in the "create" page ,  I can see it only if I try to create the document library in the parent site ( root site collection ), any ideas why this happens and how to make the saved list templates available for use in any sub site  ?

Note : SharePoint version is MOSS 2007 Enterprise