I have two fields on my form:
<field:select field="sites" id="c_com_bc_elixir_domain_Issue_sites" itemValue="_id" items="${sites}" multiple="true" path="/sites" z="f/npfl6XVF6p2FRmaqaxLAXOVrw="/>
<field:select field="category" id="c_com_bc_elixir_domain_Issue_category" itemValue="id" items="${categorys}" path="/categorys" z="vR+0nBeIl6BhamtdnQuFbV2j8iA="/>

I'm trying to call the onchange event:
dojo.addOnLoad(function() {
dojo.connect(dijit.byId("_sites"), "onchange", function(){
alert("WORKS");
});
})
dojo.addOnLoad(function() {
dojo.connect(dijit.byId("_category"), "onchange", function(){
alert("Doesn't work");
});
})

Can anyone help? The only difference is the multile="true" and if I remove the multiple="true" from the sites field it quits working.