lex autotools help

I hope this is a good list to ask...
I'm doing a rhythmbox patch that adds a .l (lex file);
it compiles to a C file and then to a .o .
How do I integrate lex with the autoconf/automake stuff?

(First thing I tried was add the .c/.h to the short Makefile.am , and
then run automake, but apparently it broke ./configure and some
makefiles. Maybe it means Makefile.am is bogus and should be ignored. I
don't want to just add the c file anyway since it is compiled.)