my spellbook isn't working

[Sven Crouse <svenc snet net>]

Hi list.  When I try to use a function from 
~/.gnumeric/1.4.3/plugins/myfuncs the cell displays "Function 
Implementation not available."  I've followed the help example and even 
tried duplicating some of the included functions 
(/usr/lib/gnumeric/plugins....).  Can somebody help me to realize what 
is happening ?  Included below are relevant files:

~/.gnumeric/1.4.3/plugins/myfuncs/plugin.xml
<plugin id="Gnumeric_MyFuncPlugin">
       <information>
               <name>My Local Python functions</name>
               <description>Sample Python plugin providing some 
(useless) functions.</description>
       </information>
       <loader type="Gnumeric_PythonLoader:python">
               <attribute value="rocket" name="module_name"/>
       </loader>
       <services>
               <service type="function_group" id="example">
                       <category>Local Python</category>
                       <functions>
                               <function name="py_add"/>
                       </functions>
               </service>
       </services>
</plugin>

~/.gnumeric/1.4.3/plugins/myfuncs/rocket.xml
from Gnumeric import GnumericError GnumericErrorVALUE
import Gnumeric
import string

def func_add(num1, num2)
       return num1 + num2

example_functions = {
       'py_add': func_add
}