pkg-config head libs

[Ilya A. Arhipov]

Hi ports@
in openttd 1.1beta* include lzma.
detect_lzma have pkg-config liblzma --modversion

%uname -rm
7.2-RELEASE amd64
%pkg-config liblzma --modversion
4.999.9beta

%uname -rm
9.0-CURRENT amd64
%pkg-config liblzma --modversion
Package liblzma was not found in the pkg-config search path.
Perhaps you should add the directory containing `liblzma.pc'
to the PKG_CONFIG_PATH environment variable
No package 'liblzma' found

How right to solve the problem?
patch to detect_lzma?
or maybe create port with head libs .pc file(for pkg-config)?

-- 
Best regard.
Ilya A. Arhipov