keyfilter is not working in primefaces mobile

I am working in jsf and primefaces 5 and creating some mobile screen.

I want to allow only numbers in my p:inputText for mobile screen.

The below code is working fine in normal screens(i.e web application) but not working for mobile screens.

<pm:field>
    <p:outputLabel value="Age" />
    <p:inputText id="age" value="#{patreg.age}">
        <pe:keyFilter mask="num"></pe:keyFilter>
        <f:ajax event="change" listener="#{patreg.generate_DOB_FromAge}" render="dob_field"/>
    </p:inputText>
</pm:field>

Is there any other way to validate/ don't allow in my p:inputText ??

Try this :

    <pm:field>
    <p:outputLabel value="Age" />
    <p:inputText id="age" value="#{patreg.age}" onkeyup="$(this).val($(this).val().replace(/[^0-9]/g, ''));" >
        <f:ajax event="change" listener="#{patreg.generate_DOB_FromAge}" render="dob_field"/>
    </p:inputText>
    </pm:field>