Following on from the Battery theme, I've created a Jaku SMS theme using the template from the Jaku iOS theme by William Szilveszter. (www.szilveszter.ca)
The Jaku theme can be purchased on Cydia.
______________________________________
To install, place in your WinterBoard themes folder.
Confirmed working on iOS 5/6, let me know if you come across any bugs.
ImageBubbleMask@2x~iphone.png is the wrong image, and SendButtonDisabled@2x.png is not consistent with the other send buttons. Other than two those minor problems, great theme.