Java 7 build 44 improves jar build speed a lot indeed

Hi,

from the changelog of jdk7 build 44, one can read that they improved on the speed of the jar task.

Indeed, I can confirm this for building JRuby which is quite a large project:

Before, Java 7 build 43:
>ant-jar complete
[...]
BUILD SUCCESSFUL
Total time: 1m30 seconds


Now, Java 7 build 44:
>ant-jar complete
[...]
BUILD SUCCESSFUL
Total time: 56 seconds


Quite enjoyable indeed!