Not sure if this will help, but here is the source code I am using.
Code:
<!-- Ammunition portal -->
<portal
id="grWeapAmmo"
style="tblNormal">
<table_dynamic
component="Gear"
showtemplate="SimpleItem"
choosetemplate="SimpleItem"
alwaysupdate="yes"
scrollable="yes"
addpick="WeapHelper"
headerpick="WeapHelper"
candidatepick="WeapHelper"
candidatefield="AmmoAllow">
<list>component.Ammunition</list>
<titlebar><![CDATA[
@text = "Add Ammunition"
]]></titlebar>
<headertitle><![CDATA[
@text = "Ammunition"
]]></headertitle>
<additem><![CDATA[
@text = "Add Ammunition"
]]></additem>
</table_dynamic>
</portal>
<!-- Modifications portal -->
<portal
id="grMods"
style="tblNormal">
<table_dynamic
component="Gear"
showtemplate="SimpleItem"
choosetemplate="SimpleItem"
alwaysupdate="yes"
scrollable="yes"
addpick="ModHelper"
headerpick="ModHelper"
candidatepick="ModHelper"
candidatefield="AllowMods">
<list>component.Mods</list>
<titlebar><![CDATA[
@text = "Add Modifications"
]]></titlebar>
<headertitle><![CDATA[
@text = "Modifications"
]]></headertitle>
<additem><![CDATA[
@text = "Add New Modifications"
]]></additem>
</table_dynamic>
</portal>