Up until v4 everything in RapidSpell Web was JSP Tag based and nothing was Javascript client based. During this period of time other technologies have been released, such as JSF, JQuery, etc - the trend has been for developers to be more Javascript aware. With multiple 'form factors' in use, it makes sense for RapidSpell Web v4 to become Javascript based, which has advantages;
The examples section includes examples using both JS and tag based modes of usage.
The Javascript method and JSP Tags are incompatible and must not both be used on the same page.