IPython launching error with Enthought Python Distribution

I have an Academic license with Enthought Python Distribution, and I'm getting a strange error when I try to run ipython. Here is some of the behavior I'm seeing:

$ ipython
Traceback (most recent call last):
  File "/Library/Frameworks/EPD64.framework/Versions/Current/bin/ipython", line 8, in <module>
    from IPython import start_ipython
ImportError: cannot import name start_ipython

$ python
Enthought Python Distribution -- www.enthought.com
Version: 7.3-2 (64-bit)

Python 2.7.2 |EPD 7.3-2 (64-bit)| (default, Sep  7 2011, 16:31:15)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "credits", "demo" or "enthought" for more information.
>>> import IPython
>>> IPython.start_ipython()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'start_ipython'
>>>

When I run the enpkg enstaller, it updated ipython and it looked like everything worked OK.

$ sudo enpkg ipython
prefix: /Library/Frameworks/EPD64.framework/Versions/7.2
No update necessary, 'ipython' is up-to-date.
ipython-1.1.0-6.egg was installed on: Sun Jan 19 23:57:27 2014

$ which ipython
/Library/Frameworks/EPD64.framework/Versions/Current/bin/ipython

$ which python
/Library/Frameworks/EPD64.framework/Versions/Current/bin/python

Any help or suggestions what I can do to get ipython to work again?

Solution

Ok after looking around, I found a problem where someone said another install of ipython might be causing problems. enpkg is trying to install ipython 1.1.0 but I still had 0.13.1 around. So I removed it via:

$ sudo rm -rf /Library/Frameworks/EPD64.framework/Versions/7.2/lib/python2.7/site-packages/ipython-0.13.1-py2.7.egg

Then it loaded with errors about kernmagic so:

$ sudo enpkg kernmagic

It somehow re-installed ipython 1.0

$ ipython
Python 2.7.2 |EPD 7.3-2 (64-bit)| (default, Sep  7 2011, 16:31:15)
Type "copyright", "credits" or "license" for more information.

IPython 1.0.0 -- An enhanced Interactive Python.

So simply re-trying the enpkg command installs the latest version.

$ sudo enpkg ipython
prefix: /Library/Frameworks/EPD64.framework/Versions/7.2
ipython-1.0.0-2.egg                                                [removing]
 12.84 MB [.................................................................]
Jinja2-2.6-2.egg                                                   [removing]
  1.58 MB [.................................................................]
tornado-2.2-1.egg                                                  [removing]
  1.42 MB [.................................................................]
tornado-3.1.1-1.egg                                              [installing]
  2.16 MB [.................................................................]
Jinja2-2.7.1-1.egg                                               [installing]
  1.62 MB [.................................................................]
ipython-1.1.0-6.egg                                              [installing]
 12.92 MB [.................................................................]

$ ipython
Python 2.7.2 |EPD 7.3-2 (64-bit)| (default, Sep  7 2011, 16:31:15)
Type "copyright", "credits" or "license" for more information.

IPython 1.1.0 -- An enhanced Interactive Python.

And now it runs without errors. So, hopefully that helps anyone else coming across these kinds of problems.