Xen users - Sep 2012 - xl: symbol lookup error: xl: undefined symbol: libxl_childproc_setmode

Hi,

I have just compiled xen 4.2.1-pre changeset 25862 from sources. When I 
tried to execute "sudo xl list" or "sudo xl info", it gave
me the
following error:

xl: symbol lookup error: xl: undefined symbol: libxl_childproc_setmode

Anybody knows how to solve this problem?

Thank you very much.

-- 
Yours sincerely,

Mr. Teo En Ming (Zhang Enming)
Singapore