xref a subheading within a node

[Phil Muldoon <pmuldoon at redhat dot com>]

I want to cross reference a particular subheading in the MI node of
the GDB patch I am writing.  So in the node:

@node GDB/MI Program Execution
@section @sc{gdb/mi} Program Execution

I want my @xref to point directly at the @subheading:

@subheading The @code{-stack-list-frames} Command
@findex -stack-list-frames

But my @xref:

@xref{GDB/MI Program Execution,, The -stack-list-frames Command}.

While it works, in the PDF output only points to the beginning of the
node:

see Section 27.14 [The -stack-list-frames Command], page 384.

This is a large section so I was hoping for more accuracy than that.

Any help would be appreciated.

Cheers,

Phil