13. A computer-implemented method of detecting and preventing leakage of sensitive documents from a particular organization, comprising: using a data leak prevention application to select a sensitivity category for a document based on a size of the document, a data type and a protocol of the document, the sensitivity category reflecting an extent to which leakage of the document out of the organization would harm that particular organization; checking a source and destination of the document if the protocol is for email; a user configuring interaction of a scripting language processing engine with the data leak prevention application to activate code portions of the scripting language processing engine at a run time event of the data leak prevention application, the scripting language processing engine embedded in the data leak prevention application and having access to data accessible to the data leak prevention application; using the scripting language processing engine to validate the data type of the document; re-selecting a sensitivity category for the document based on the validation; and using the data leak prevention application containing the embedded scripting language processing engine to perform an action to prevent data leakage of the document out of the organization based on the re-selection of the sensitivity category for the document.
13. A computer-implemented method of detecting and preventing leakage of sensitive documents from a particular organization, comprising: using a data leak prevention application to select a sensitivity category for a document based on a size of the document, a data type and a protocol of the document, the sensitivity category reflecting an extent to which leakage of the document out of the organization would harm that particular organization; checking a source and destination of the document if the protocol is for email; a user configuring interaction of a scripting language processing engine with the data leak prevention application to activate code portions of the scripting language processing engine at a run time event of the data leak prevention application, the scripting language processing engine embedded in the data leak prevention application and having access to data accessible to the data leak prevention application; using the scripting language processing engine to validate the data type of the document; re-selecting a sensitivity category for the document based on the validation; and using the data leak prevention application containing the embedded scripting language processing engine to perform an action to prevent data leakage of the document out of the organization based on the re-selection of the sensitivity category for the document. 16. The method of claim 13 , further including selecting the sensitivity category of the document based on a data type characterized by a frequency that an identification number occurs in the document, the identification number identifying an individual customer, individual subscriber, individual citizen or individual member of the particular organization, the identification number occurring in the document unrelated to any step performed by the data leak prevention application applied on the document.