I have two apps which basically use the exact same code and have a generic error page to catch exceptions of type Throwable. It works in one, but not the other. The only difference is the one that isn't working is using frames. In both cases I have a custom tag on the error page (that is defined in web.xml) which captures the exception information and emails it to the development team. The tag on the error page which is in the app which uses frames is indicating that pageContext.getException() is returning null. I have <%@ page isErrorPage="true" %> on both of my error pages. Just in case It ignored the isErrorPage since it is a framed page, I also put isErrorPage on the parent as well, but to no avail. Has anyone seen this before, or does anyone have any ideas?