Why extern variables and functions within template/struct/class have a D mangling

[Igor Stepanov]

Is it correct?
When I wrote next code:
template Extern(string s)
{
     mixin("static extern(C) extern int "~s~";"~
     "alias Extern = "~s~";");
}
void main()
{
     writeln(&Extern!("xxx"));
}
I get error message "undefined reference to 
`_D1a24__T6ExternVAyaa3_787878Z3xxxi'", when I expect to get 
"undefined reference to `xxx'"?
Is it error?