[Zope] keyword args where the keyword is a variable in dtml

I want to change the following dtml which works: <!--#var expr=getPropertyType('default') --> <!--#if "hasProperty('lastValue')"--> <!--#call "manage_changeProperties(lastValue=newval)"--> <!--#else--> <!--#var expr=getPropertyType('default') --> <!--#call "manage_addProperty('lastValue',newval,getPropertyType('default'))"--> <!--#/if--> to somethiong where 'lastValue' is a parameter. The problem is manage_changeProperties(lastValue=newval) takes keyword args and I am not sure how to prepare to pass the args if lastValue is the value of some variable. Regards, Albert