rhskold,
You do not need 2 licenses.You can activate MyEclipse on different machines using the same license key, but you need to make sure that at any given point the number of instances of MyEclipse opened on these machines do not exceed the no of users restriction for the license.
For example : If you are on a single user license and login from multiple system, then MyEclipse would prompt you that too many users are using the subscription key. It will also list the IPs using this key. If you wish to use single-user license ensure that at any given time you are not logged in from multiple machine using the same license key.
Let us know if you see any issues.