Could not convert HTML part to text

[Jack <ostroffjh users sourceforge net>]

I've finally got the git gtk3 branch compiled, but whenever it  
downloads new messages, I get a string of errors 'Could not convert  
HTML part to text: Failed to execute child process "" (No such file or  
directory)'.  That message is from libbalsa/html.c, with the failing  
function libbalsa_message_body_get_content.  I have no problem actually  
viewing HTML mime parts, and ldd doesn't show any missing libraries.  I  
also do not see any error messages on the console if run from command  
line.

I would eventually try to track this down with gdb, but hopefully  
someone here will quickly recognize what stupid thing I've done in the  
configuration.

Thanks for any pointers.

Jack

----------------- my ./configure invocation:
./configure --prefix=/usr/local \
--build=x86_64-pc-linux-gnu \
--host=x86_64-pc-linux-gnu \
--with-gpgme \
--with-html-widget=webkit \
--enable-smime \
--without-gnome \
--without-gtksourceview \
--with-spell-checker=gtkspell \
--without-gss \
--without-ldap \
--without-libsecret \
--without-rubrica \
--without-sqlite