GWT-Gadgets org.apache.xerces.jaxp.SAXParserFactoryImpl not found - OR - org.w3c.dom.DOMException: NAMESPACE_ERR

[GoogleCodeExporter]

Found in Release:
gwt-gadgets 1.2.1

Platform information (OS, Browser, GWT version). 
Eclipse Google Plug-In 2.5.0
GWT SDK 2.4.0
App Engine SDK 1.6.1

Does the issue exist on other platforms?
Unknown

Give a Detailed description of the problem.  If possible, please include some 
code that reproduces the problem and a verbatim copy of any error messages you 
can find.
Attempting to run an application in development mode using "Run As > Web 
Application" results in the error "org.apache.xerces.jaxp.SAXParserFactoryImpl 
not found"
Replacing the gwt-gadgets.jar with gwt-gadgets-noredist.jar fixes this problem, 
but causes another:  Attempting a GWT compile with the gwt-gadgets-noredist.jar 
causes the error "org.w3c.dom.DOMException: NAMESPACE_ERR"

Workaround if you have one:
Switch back and forth between the gwt-gadgets.jar and the 
gwt-gadgets-noredist.jar between running locally in development mode, and 
compiling/deploying to App Engine.

Original issue reported on code.google.com by cw...@cloudsherpas.com on 23 Jan 2012 at 10:25

[GoogleCodeExporter]

Have a solution been found?  Can't compile my gadget since I've moved from GWT 
2.1.1 to 2.5.1. Thanx for your help.

Original comment by f.masu...@gmail.com on 25 May 2013 at 9:04

[GoogleCodeExporter]

Ok, found a solution for my NAMESPACE_ERR : just had to put GWT SDK library 
earlier in the classpath before referenced librairies.  It compiles just fine 
now.

Original comment by f.masu...@gmail.com on 25 May 2013 at 9:10