I found a great workaround for building with jenkins.
First, before setting up the job, download the jenkins plugin with the name:
Parameterized Trigger Plugin
https://wiki.jenkins-ci.org/display/JENKINS/Parameterized+Trigger+Plugin
Once you do this, create your task and when creating the task, select
'This assembly is parameterized.'
Create a string parameter. I call my CODE_SIGN_IDENTITY.
So, the name field in the String parameter should be:
Name: CODE_SIGN_IDENTITY
Default value: iPhone Developer: XXX XXXXX
Description: whatever you post there
Then, in your Xcode Plugin, find the "xcodebuild Custom Arguments" field.
In the xcodebuild Custom Arguments field, put the following value:
CODE_SIGN_IDENTITY = $ {CODE_SIGN_IDENTITY}
Complete the setup of your work, and you must be tuned!
This will do without spaces. The plugin is a life saver, because it works great, and you can customize your assembly with other parameters.