problems with jars

I just finished my first project at my new job, and now i need to package it into a jar so it can be executed with a double click. I am using Eclipse to develop it, and it works fine within eclipse. However, after I export the project to a jar from eclipse it gives me this error during runtime

C:\Documents and Settings\Greg MacPherson\Desktop>java -jar ProgrammingUtility.j

ar

Exception in thread"UT2" java.lang.NoClassDefFoundError: org/apache/commons/net

/tftp/TFTPClient

at com.******.programmer.util.Tftp.tftp(Tftp.java:48)

at com.******.programmer.UploadThread.upload_cobs(UploadFirmware.java:38

4)

at com.******.programmer.UploadThread.run(UploadFirmware.java:683)

(the ****** is the name of my company )

it seems like for some reason eclipse isn't adding that package into the jar. Anyone have any idea how to get this to work?

in case it helps, these are the settings i'm using while exporting the jar:

http://img467.imageshack.us/my.php?image=screen1uz7.png

http://img467.imageshack.us/my.php?image=screen1uz7.png

http://img406.imageshack.us/my.php?image=screen3bu4.png (this one might take a while to load for some reason)

thanks

[1269 byte] By [Greg.MacPhersona] at [2007-11-27 6:03:49]
# 1
i also forgot to mention that the jar will work fine up until the point it needs this library(after i click on one of the buttons in the application)also, if no one here can help me, does anyone have a link to the eclipse forums? i couldn't find it on their website
Greg.MacPhersona at 2007-7-12 16:47:00 > top of Java-index,Java Essentials,Java Programming...
# 2
You have to have the Apache jar available and on the classpath for Java to find it.And Eclipse has mailing lists, not forums.
ChuckBinga at 2007-7-12 16:47:00 > top of Java-index,Java Essentials,Java Programming...
# 3
i managed to get it working by copying the contents of that package directly into the jar. might not be the best way, but it worked.
Greg.MacPhersona at 2007-7-12 16:47:00 > top of Java-index,Java Essentials,Java Programming...
# 4
It definitely is not the best way, you should have the supporting library as a separate jar and add that to the classpath of your own jar.
dwga at 2007-7-12 16:47:00 > top of Java-index,Java Essentials,Java Programming...