See the details at https://github.com/mybatis/mybatis-3/issues?milestone=4&page=1&state=closed
This version calculates bindings during startup for all statements that are not dynamic, so there is no longer needed to use lang="raw" to improve performance. See issue #98.
An special remark about this feature. Previous versions ignored the "parameterType" attribute and used the actual parameter to calculate bindings. This version builds the binding information during startup and the "parameterType" attribute is used if present (though it is still optional), so in case you had a wrong value for it you will have to change it.