Steps to reproduce:
1) Install as your current username, by editing org.jenkins-ci.plist
For UserName use Mac OS X username.
restart Jenkins
2) Create Build a free-style software project
3) Source Code Management : None
4) Xcode
i) Clean before build? Yes
ii) Target : Give a target Name.
iiI) Configuration: Debug
iv) Xcode Project File : give path to current ProjectName.xcodeproj
v) Build IPA? Yes
vi) Keychain path : ${HOME}/Library/Keychains/login.keychain
vii) Save
5) Now Hit Build Now
Xcode project builds fine, but results in failed build.
All Objective-C files are built fine.
Examining console log, at bottom:

• • BUILD SUCCEEDED **

Cleaning up previously generate .ipa files
FATAL: /Users/pjmurphy/Jenkins/Home/jobs/Release1/workspace/build/Debug-iphoneos does not exist.
/Users/pjmurphy/Jenkins/Home/jobs/Release1/workspace/build/Debug-iphoneos does not exist.

Some file permission issue exists with creating /workspace/build/Debug-iphoneos. This directory is built in the users home directory so why this exists is a mystery.
If you check off Build IPA : No, everything builds fine, and there is no FATAL error.
In addition if you give it a Git Hub project, and in Xcode : check Build IPA : YES, it also works fine.

We want to use this tool to build our iPhone Apps, but the current IPA bug prevents us from doing so.
Please fix.
Thanks...