Compile problem on BSDi 3.0

I suppose this is an oldie but goodie, but I need a clue.

I've got BSDi 3.0 on an i386 platform. Following the installation
instructions for pgsql, I upgraded flex to 2.5.4 using the 2.5.4a download
from prep.ai.mit.edu. However, when I run gmake, I get this failure
sequence:

-----------

gmake lexverify
gmake[1]: Entering directory `/usr2/src/pgsql/src'
gmake -C lextest all
gmake[2]: Entering directory `/usr2/src/pgsql/src/lextest'
lex scan.l
gcc2 -c lex.yy.c
gcc2 -c lextest.c
gcc2 -o lextest lex.yy.o lextest.o
unexpected last match in input()
gmake[2]: Leaving directory `/usr2/src/pgsql/src/lextest'

You have a buggy version of flex.  Read INSTALL and search for flex for a
fix.

gmake[1]: *** [lexverify] Error 1
gmake[1]: Leaving directory `/usr2/src/pgsql/src'
gmake: *** [all] Error 2

--------------

My gcc is version 2.7.2.1, flex reports version 2.5.4.

Can I buy a clue from someone?

Thanks,
Gary

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* Gary B. Hoffman, Computing Services Manager  e-mail: ghoffman@ucsd.edu *
* Graduate School of International Relations and Pacific Studies (IR/PS) *
* University of California, San Diego (UCSD)       voice: (619) 534-1989 *
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