yes i added to the classpath property, I'm using this:
sencha compile -classpath=c:/inetpub/wwwroot/CommonFiles/ExtJS-4.1.1/src,JavaScript/js,JavaScript/app,JavaScript/libs/extensible/src ...

Code:
[INF]           Processing source dependencies[ERR]           Failed to find file for Extensible.calendar.data.EventMappings
 required by c:\Projects\AttendanceSheet\trunk\JavascriptSource\JavaScript\libs\extensible\src\calendar\form\EventDetails.js
[ERR]           Failed to find any files for Extensible.calendar.data.EventMappings
because in the EventMappings.js the source code look like this:
Code:
Ext.ns('Extensible.calendar.data');

Extensible.calendar.data.EventMappings = {