Problem installing optim package on Mac OS X

[Mic Miller]

I am running Octave version 3.2.0 on a MacBook running OS X Leopard v10.5.8:
octave-3.2.0:10> version
ans = 3.2.0

I want to install the signal processing package which has the miscellaneous, 
optim, and specfun packages listed as dependencies:
octave-3.2.0:11> ls
miscellaneous-1.0.9.tar 
signal-1.0.10.tar
optim-1.0.10.tar 
specfun-1.0.8.tar

The miscellaneous package installed without errors. 

Several errors are thrown trying to install optim:
octave-3.2.0:12> pkg install optim-1.0.10.tar
mkoctfile: stripping disabled on this platform
mkoctfile: stripping disabled on this platform
__bfgsmin.cc: In function ‘int __newtonstep(double&, double&, std::string, 
octave_value_list, ColumnVector, ColumnVector, int, int)’:
__bfgsmin.cc:242: error: ‘isnan’ was not declared in this scope
make: *** [__bfgsmin.oct] Error 1
'make' returned the following error: mkoctfile -s leval.cc
mkoctfile -s __bfgsmin.cc
error: called from `pkg>configure_make' in file 
/Applications/Octave.app/Contents/Resources/share/octave/3.2.0/m/pkg/pkg.m near 
line 1253, column 2
error: called from:
error: 
/Applications/Octave.app/Contents/Resources/share/octave/3.2.0/m/pkg/pkg.m at 
line 714, column 5
error: 
/Applications/Octave.app/Contents/Resources/share/octave/3.2.0/m/pkg/pkg.m at 
line 287, column 7

Only two errors were thrown on specfun. These were apparently not fatal, as 
specfun is shown as installed (see below):
octave-3.2.0:12> pkg install specfun-1.0.8.tar
mkoctfile: stripping disabled on this platform
warning: gen_doc_cache: unusable help text in 'test_sncndn'. Ignoring function.

signal would not install because of optim dependency:
octave-3.2.0:13> pkg install signal-1.0.10.tar
error: the following dependencies where unsatisfied:
signal needs optim >= 1.0.0

pkg list shows that miscellaneous and specfun installed:
octave-3.2.0:13> pkg list
Package Name | Version | Installation directory
---------------+---------+-----------------------
miscellaneous *| 1.0.9 | /Users/mic/octave/miscellaneous-1.0.9
specfun *| 1.0.8 | /Users/mic/octave/specfun-1.0.8


I am new to the list, somewhat new to Octave and the Mac.  I haven't had any 
success searching for a solution through Google.  I downloaded the most recent 
version of optim-1.0.12 but it threw the same errors. Any suggestions how to 
get optim to install would be welcome.

Thanks,

Mic