This is weird...

I changed the line back to read like the original file found in the grx24s.zip package, and it compiles with no complains. So I suspect an 'invisible' char in that line that was confusing gcc. Viewing the original file through a hex viewer didn't show anything. Then I unzipped and recompiled the original package again... everything went ok. I don't know what to say... I feel so dumb...

Best regards, Norberto