Solaris - make failure

Getting the following error when installing the ferret-0.11.4.gem on a
Solaris box. Any ideas on how to fix this or what is going wrong?

In file included from q_multi_term.c:2:
search.h:716: field ‘comparables’ has incomplete type
q_multi_term.c: In function ‘multi-tq_new_conf’:
q_multi_term.c:634: ‘func’ undeclared (first use in this function)
q_multi_term.c:634: (Each undeclared identifier is reported only once
q_mulit_term.c:634: for each function it appears in.)
make: Fatal error: Command failed for target ‘q_multi_term.o’
rub extconf.rb install ferret-0.11.4.gem
creating Makefile

make
gcc -I. -I/xxx/yyy/ruby/lib/ruby/1.8/sparc-solaris2.10 -I/xxx/yyy/ruby
/lib/ruby/1.8/sparc-solaris2.10 -I. -fPIC -g -02 -D_File_OFFSET_BITS=64
-c q_mu lit_term.c
*** Error code 1

make install
gcc -I. -I/xxx/yyy/ruby/lib/ruby/1.8/sparc-solaris2.10 -I/xxx/yyy/ruby
/lib/ruby/1.8/sparc-solaris2.10 -I. -fPIC -g -02 -D_File_OFFSET_BITS=64
-c q_mu lit_term.c
*** Error code 1