Cannot deserialize dynamic proxies

A serialized dynamic proxy looks like this:

<-Proxy0 id="1"> ...

Upon deserialization:

org.xmlpull.v1.XmlPullParserException: expected start tag name and not - (position: START_DOCUMENT seen <-... @1:2)

Reason:

• $ is a valid char in class names.
• XStream will rewrite $ chars with - chars (as $ isn't a valid char in XML elements).
• Dynamic proxies are named $ProxyN which is renamed to -ProxyN.
• XPP3 appears to barf on element names that start with -. <hello-world> is good. <-world> is bad.