[plt-scheme] Problems building plt scheme 370 under FreeBSD 6.2 with --enable-shared

Building plt scheme 370 under FreeBSD 6.2 without --enable-shared
seemd to work fine.  Building with it *with* --enable-shared fails
with the error

> libtool: link: cannot find the library `'

Here's the last bit of the log:

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Any suggestions?  (The only other argument to configure was
"--prefix=/sw/versions/plt/370-shared".) 
-- 
T. Kurt Bond, tkb at tkb.mpl.com