hudson.Util.VARIABLE defines a pattern for variable names, which excludes variables names with a '.' in them. The current definition is:

private static final Pattern VARIABLE = Pattern.compile("\\$([A-Za-z0-9_]+|

|
$)");

However, variables with '.' are commonplace. For example, see the standard list of Java environment variables here: http://download.oracle.com/javase/6/docs/api/java/lang/System.html#getProperties%28%29

Please consider updating the VARIABLE declaration to include names with a '.', such as:

private static final Pattern VARIABLE = Pattern.compile("\\$([A-Za-z0-9_\\.]+|

|
$)");

Unfortunately, I have had extraordinary difficulty trying to get the hudson core checked out as Eclipse projects, so that I can test the change. So, I admit that I have not tested the specific change above. Hopefully, it would be easy to verify.

Thanks!
– Scott