Editing the PrimeFaces code would be the last option to take.
There was already a similar issue, take a look at this page:
The solution for you could be something like:
<p:inplace editor="true">
<f:facet name="output">
<h:outputText value="#{yourBean.text}" escape="false" />
</f:facet>
<f:facet name="input">
<p:inputText value="#{yourBean.text}" />
</f:facet>
</p:inplace>