XP is agile and extreme. If management is bad, XP makes the worst enemy out of it, so that the management is undefined :)
CRC cards can be used regardless of the process for as long as you follow OOP, same for prototyping which I'd expect mentioned here.
In XP, the idea is typically first coded as a small prototype and then either thrown away for a better idea, or refactored into the final solution. (details)
This is one important aspect of XP which you won't achieve by remote collaboration. A couple of programmers (not a love couple) sits at the same table with just one keyboard. While one person writes the code the other is meant to correct him or suggest useful improvements. (details)
XP is iterative and incremental. There can be a release plan with features on the CRC cards and the schedule in which they are meant to be implemented. For every planned release, pile up some cards. Be careful not to exceed the available slot. You need to be measuring whether all those cards fit in, as explained in the next point.
Release & Iteration Planning
First take one CRC card which you consider a small task, implement it, measure it, and then try to size the card to other cards. How many times bigger are the tasks on other cards compared to the card you've taken for your sizing? Use this technique to roughly estimate the size, so that you can stuff the right amount of work into each iteration.
The biggest risk of XP, in my opinion, is unnecessary rework caused by unclear / unstable requirements or too much refactoring caused by the two programmers striving for perfection. Secondly, there is a risk the two programmers won't get along well. This may happen surprisingly often, providing they haven't been working together previously in this setup. XP is still a big experiment. I wouldn't consider it as reliable and dependable as conventional techniques such as the Unified Process.
This is up to you to decide. Where may XP apply well and why?
Although I am unaware of any specific XP project management software, other software may fit the purpose, such as CASE tools supporting CRC modelling and any Agile release / iteration planning software.
QuickCRC, Visual Paradigm, others. (CRC)
Atlassian Greenhopper, VersionOne, Extreme Planner (Release / Iteration planning)
Since you are collaborating remotely, consider also using some team collaboration software, such as Atlassian JIRA.