Ruby script/plugin install not working

I have mingGW32 , and cygdrive …

I made a git clone … perfect…

I intent to use git… $ ./script/plugin install git://…
it did not work, PLUGIN NOT FOUND…

I used in the console C:\ Windows\system32\cmd.exe

C:\ path…>.ruby script\plugin install git:// or… http://

it works…
but

It copy only the dir carpets or foulders …

RAILS … /vendor/plugin/2dc_qgrid/ …
but at the end the carpet 2dc_… is empty…

Can you help me… I spend much time…

the plugin is…2dc_jqgrid.git…