what to do about "FATAL: PLIST_FILES: files cannot contain %%FOO%% variables. Use make variables and logic instead"

[Ronald Klop]

Hi,

I was looking for a change to devel/jna and after running portlint it says:

FATAL: PLIST_FILES: files cannot contain %%FOO%% variables.  Use make variables 
and logic instead

The lines in the Makefile this is about are:
PLIST_FILES=    %%JAVAJARDIR%%/jna-platform.jar \
               %%JAVAJARDIR%%/jna.jar

What would be the proper solution for this?

Regards,
Ronald.