Java EE (Java Enterprise Edition) General Discussion

Hi. I'm trying to modify a jsp that opens a runtime generated pdf. Originally, the pdf is opened by prompting the Adobe Reader program, but now I need to open the pdf within the jsp (which also have other content, not just display the pdf). I tried to embed the pdf in an iframe (similar to this: http://www.cs.tut.fi/~jkorpela/html/iframe-pdf.html ), but not works, it still prompts the Adobe Reader program. Actually the pdf content is generated on runtime and output through a servlet's output stream (this servlet is written by someone already left), what i did is try to open this servlet url in an iframe. If the iframe src is really a pdf file, it really works. But now the url is a servlet that output a pdf, is there anything special needed to do in the servlet in order to fulfill my requirement?