The maximum supported width value of tootip is not enough
- Detailed description of the problem
When the width of tootip is bigger than 500 pixels, the border will have rendering problems. From the javadoc of the super class "Tip", the "The maximum supported value is 500" pixels. This seems to be arbitrary and un-reasonable as we do have use case that require tooltip that is wider than 500 pixels. I guess that reason for this is that the background image used for tootip, "tip-sprite.gif" is only 500 pixels wide. If that is the reason, it should be easy to make the image wider and tootip can have bigger width.
As it is suggested above. make the "tip-sprite.gif" wider