configure failure in ports build on current

[Derek Tattersall]

I attempted to build gtk20 on my AMD64 current box.  It fails in the
configure step as follows:
checking for TIFFReadScanline in -ltiff... no
checking for TIFFWriteScanline in -ltiff... no
checking for TIFFFlushData in -ltiff34... no
configure: WARNING: *** TIFF loader will not be built (TIFF library not
found) ***
configure: error:
*** Checks for TIFF loader failed. You can build without it by passing
*** --without-libtiff to configure but some programs using GTK+ may
*** not work properly
===>  Script "configure" failed unexpectedly.

However, nm /usr/local/lib/libtiff.so shows:
000000000002df90 T TIFFReadScanline
000000000002e450 T TIFFScanlineSize
0000000000030890 T TIFFWriteScanline

00000000000176b0 T TIFFFlushData

Building on 6.2 Stable AMD64 has no problems.  I also note that libtiff
on Stable is also in /usr/local/lib.  

Is there some environment variable that I haven't set in the current
box, or what?  Does anybody have a clue for me?

-- 
Best regards,
Derek Tattersall
dlt at mebtel.net		dlt666 at yahoo.com		 dtatters at gmail.com