Yes, I ran into this as well. It is a security issue with oracle. They do not allow you to log into the database as user sys from over the web. The solution is very easy though. Create a different user for yourself and give yourself the dba role permission.
Create user you identified by youpassword Grant dba to you
then logon thought isqlplus with this user.
I am using oracle 10g when I ran into this issue.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com