Vim and snipMate (plugin) - adding new snippet won't work -

i trying create new snippet snipmate plugin.

i work files called (i.e.) myfile.endfile

all .endfile files should have same "snippet" .html files. did

cp html.snippet endfile.snippet 

in ~/.vim/snippets directory.

snipmate working present snippets, not new created one. suggestions problem?

(btw: after creating new .snippet file, ran :helptags ~/.vim/doc command in vim instance.)

it because snipmate works filetype, vim option set when opening file of particular type.

for exemple, if opening, "index.html" filetype automatically set html.

to see how works, :
:e $vimruntime/filetype.vim

as preliminary test, can :
1. open test.endfile
2. type :set ft=endfile or :set filetype=endfile
3. check if defined snippets work

to automatically add following in .vimrc :
au bufnewfile,bufread *.endfile set filetype=endfile

it means every time read or create new file ending in endfilethe filetype option set endfile.

(the filetype arbitrary string doesn't have identical file extension)