I have 2 linked combos, and they work, except for it seems that the filter doesn't see a differance between 2 of the options. 'USG' and 'USG M'. USG M filters as it should, but USG includes the options for both?

Readers:
PHP Code:
//readers
var fundingReader = new Ext.data.JsonReader({
    
root:'data',
    
fields: [
        {
name'fundingID'type'string'},
        {
name'fundingType'type'string'}
    ]
});
var 
DSNReader = new Ext.data.JsonReader({
    
root:'data',
    
fields: [
        {
name'fundingType'type'string'},
        {
name'DSN'type'int'},
        {
name'displayValue'type'string'}
    ]
}); 
Code:
PHP Code:
{    
layout:'column',
border:false,
items:[{
    
columnWidth:.50,
    
layout'form',
    
bodyStyle:'padding:1px',
    
border:false,
    
items: [
            new 
Ext.form.ComboBox({
            
storefundingddDS,
            
waitMsgTargettrue,
            
listeners:{select:{fn:function(combovalue) {
                var 
Ext.getCmp('dsnDonor');  
                
i.enable();
                
i.clearValue();
                
i.store.filter('fundingType'this.getValue());
            }}},
            
fieldLabel'<nobr> Funding Type</nobr>',
            
id'funding_type',
            
title:'Funding Type',
            
labelStyle'font-weight:bold; width:165;',
            
name'funding_type',
            
displayField:'fundingType',
            
valueField'fundingID',
            
hiddenName'fundingID',
            
triggerAction'all',
            
forceSelection:true,
            
typeAhead:true
            
mode'local',                    //uses ds already loaded
            
emptyText:'Select Funding Type...',
            
selectOnFocus:true,
            
allowBlank:false
            
})
            ]
},{
    
columnWidth:.50,
    
layout'form',
    
bodyStyle:'padding:1px',
    
border:false,
        
items: [
            new 
Ext.form.ComboBox({
            
storeDSNddDS,
            
waitMsgTargettrue,
            
fieldLabel'<nobr>  DSN/Donor Source Name</nobr>',
            
id'dsnDonor',
            
title:'DSN - Donor Source Name',
            
labelStyle'font-weight:bold; width:165;',
            
name'dsnDonor',
            
displayField:'displayValue',
            
valueField'DSN',
            
hiddenName'DSN',
            
triggerAction'all',
            
forceSelection:true,
            
typeAhead:true
            
mode'local',                    //uses ds already loaded
            
emptyText:'Select a DSN/Donor Source Name...',
            
selectOnFocus:true,
            
allowBlank:false,
            
disabledtrue,
            
lastQuery:''
            
})
        ]
}]