Is it possible to change the predefind Bootstrap classes set in the Bootstrap theme in ExtLib

I am using the responsive Bootstrap theme together with the application layout control in extlib and cannot really find any documentation about if it is possible to change the Bootstrap predefined classes.

in the following example there is a titlebar with tabs using the predefined Bootstrap class "nav nav-tabs"

In my case I do not want the "nav-tabs" class, instead I want the "nav-pills" class but I find no way to change this using the source editor, I know I can change classes using client side script but I am hoping there is a server side way to control this.

<xe:this.configuration>
        <xe:bootstrapResponsiveConfiguration legal="Copyright " placeBar="true" banner="true" fixedNavbar="fixed-bottom" footer="true" invertedNavbar="true" placeBarName="#{javascript:compositeData.Title}" rightColumnLabel="RightColumnLabel" titleBar="true" defaultNavigationPath="/tab1/link1" productLogo="/logo.gif" pageWidth="full">
            <xe:this.titleBarTabs>
                    <xe:pageTreeNode label="page1" page="/page1.xsp"></xe:pageTreeNode>
                    <xe:pageTreeNode label="page2" page="/page2.xsp"></xe:pageTreeNode>
                    <xe:pageTreeNode label="page3" page="/page3.xsp"></xe:pageTreeNode>
            </xe:this.titleBarTabs>
        </xe:bootstrapResponsiveConfiguration>
</xe:this.configuration>

I have tried to add a class like this but it does nothing to the html

<xe:this.titleBarTabs styleClass="nav nav-pills">