Internal Server Error with METHOD:POST

[fusterjj <ju...@dotecengineering.com>]

Hello everyone, 
I am trying to do a simple servlet with an html form using the POST method. The html form is just a simple input form where the user enters 4 fields of data. The HTML invokes the taskserv, wich is the servlet with the post method and the driver connection to mysql database in order to insert the data in the database. The problem is that I am getting an Internal Server Error which says:
Cannot allocate servlet instance for path /servlet/taskserv; however the servlet is inside the WEB-INF directory and inside the CLASSES folder, so it should not have any problem to find the class. I have changed the code a couple of times but I am getting the same error. Does anyone know why is this happening?? Is there has to be with  my Tomcat configuration or the web.xml or the code??? 
I would really appreciate if you help me. If you are willing I can send you the code and the Exception report to make it easier.

 Thank you all!!!