Picklist dependency not working on VF page

<tr>
<td width="100px" align="left" valign="top"><font face="georgia" ><b><apex:outputLabel value="State" /></b></font></td>
<td align="left" valign="top"><apex:inputField value="{!opp.Location_State__c}"  /></td>
<td width="100px" align="left" valign="top"><font face="georgia" ><b><apex:outputLabel value="County (if applicable)" /></b></font></td>
<td align="left" valign="top"><apex:inputField value="{!opp.Location_County__c}" /></td>
</tr>

The page uses a custom controller written for this purpose.  The relevant portion of the controller (I believe) is:

public class enterServiceProjectController {
    public enterServiceProjectController() {
    ServiceProjectId = [select id from RecordType where name = 'Service Project'][0].id;
    AdvancedTrainingId = [select id from RecordType where name = 'Advanced Training'][0].id;
    SelectedPartners = new list<Account>();
    //AllOrgs = new List<Id>();
    ListPartners();
    SetUpOpp();
    ctct = new Contact();
    accountToDeleteId = '';
    ListPartners();
    }
public contact ctct {get;set;}
public account acc {get; set;}
public opportunity opp {get;set;}
public string SelectedPartner1 {get;set;}
public string SelectedPartner2 {get;set;}
public string SelectedPartner3 {get;set;}
public boolean ContactNotListed {get;Set;}
public Id ServiceProjectId{get; set;}
public Id AdvancedTrainingId{get;set;}
public string ChosenRTId {get; set;}
//public list<Id> AllOrgs {get; set;}
public map<string,account> Partnermap {get; set;}
public list<selectOPtion> Partners {get;set;}
public list<Account> SelectedPartners {get; set;}
public boolean IsThisWorking {get; set;}
    public string accountToDeleteId {get; set;}
public PageReference submitVol() {
    ContactNotListed=false;
        LIST<String> person = identifyPerson.identifyPerson(ctct);
        if (person == null) {
                ContactNotListed = true;
                return null; 
    } else {
        if (person[1]=='Contact') {
            ctct.id = person[0];
            acc = [select id from Account where id = :[select accountid from Contact where id = :ctct.id].accountid];
            pageReference nextPage = Page.enterServiceProjectPage;
            nextPage.setRedirect(false);
            return nextPage;
        } else {
            ContactNotListed = true;
            return null;
        }
    }
}
public PageReference ReviewPage() {
            pageReference nextPage = Page.enterServiceProjectReviewPage;
            nextPage.setRedirect(false);
            return nextPage;
        } 
public Opportunity setUpOpp() {
    if (opp == null) {
    opp = new Opportunity(name='autofill');
        }
    return opp;
}
public PageReference ReturnToEnterSPPage() {
pageReference nextPage = Page.enterServiceProjectPage;
            nextPage.setRedirect(false);
            return nextPage;    
    }