<a4j:commandButton> not working properly in IE

<f:view>

                <f:loadBundle basename="ErrorMessages" var="ErrMsg"/>

                <a4j:loadBundle basename="Refer" var="lbl"/>

                <a4j:form id="newAdd">

                 <jsp:include page="/messagepanel.jsp"></jsp:include>

                          <center>

                          <rich:panel id="AddActioinPanel" header="Group-#{bean.buttonActionStatus}" headerClass="pnlhdr" style="widht:95%;align:center;">

                                   <rich:toolBar itemSeparator="line" width="95%" >

                                           <rich:toolBarGroup>

                                                 <a4j:commandButton id="saveEditBtn" value="#{lbl.btnSave}"

                                                                               action="#{bean.saveOrEdit}"

                                                                                onclick="Richfaces.showModalPanel('processingMessage');" 

                                                                                oncomplete="Richfaces.hideModalPanel('processingMessage');"

                                                                                disabled="#{bean.disablebtn}"

                                                                                styleClass="btn">

                                                  </a4j:commandButton>

                                               <r/ich:toolBarGroup>

                                        </rich:toolBar>

                                           <table align="center">

                                        <tr>

                                            <td><h:outputText value="*#{lbl.Group_name}#{lbl.fieldSeparator}" styleClass="txtRightBold"></h:outputText></td>

                                            <td><h:inputText id="GroupName"

                                                                       value="#{bean.Group.name}"

                                                                       required="true"

                                                                       maxlength="75"

                                                                       validator="#{bean.validateGroupName}"

                                                                       label="#{lbl.Group_name}"

                                                                       styleClass="inputText"

                                                                       onblur="this.value = this.value.toUpperCase()">

                                                    </h:inputText>

                                            </td>

                                        </tr>

                                        <tr>

                                            <td><h:outputText value="*#{lbl.Group_status}#{lbl.fieldSeparator}" styleClass="txtRightBold"></h:outputText></td>

                                            <td><h:selectOneMenu id="GroupStatus"

                                                                                value="#{bean.Group.activeInd}"

                                                                                 required="true"

                                                                                     label="#{lbl.Group_status}">

                                                            <f:selectItem itemValue="" itemLabel="Select Status"/>

                                                            <f:selectItems value="#{bean.statusList}"/>

                                                    </h:selectOneMenu>

                                            </td>

                                        </tr>

                                    </table>

                            </rich:panel>

                        </center>                           

                  </a4j:form>

             </f:view>