Basically you'd need to combine these two validation rules:

My_Date__c - TODAY() &gt; 4


and 

CASE(MOD( My_Date__c - DATE(1900, 1, 7), 7),
0, 0,
6, 0,
1) = 0


The first obviously gives you a date that's more than 4 days from today. The 2nd gives you weekdays since the start of the year 1900. You might need to first check to see which day of the week it was, then change your criteria for My_Date__c - TODAY() &gt; 4 to My_Date__c - TODAY() &gt; 5 or 6 if its either a Tuesday or Wednesday. 

I don't know if TODAY() is allowed to be a Sat or Sun, but clearly, My_Date__c - TODAY() &gt; 4 works for that condition, so the main thing you need to check for is if TODAY() is a Tues or Wed then adjust accordingly. 

Date cannot be within x working days of today
We currently have a variety of systems (Linux, Solarix, *BSD, HP-UX ...) on which we are not allowed to install anything into / (but I have root access. That's strange, I know). But we'd like to run Puppet on all of them. So, the obvious idea is to install Puppet with all prebuilt dependencies into some isolated tree, something like "jail", which will allow to use dependences from some prefix and to access the host system. The big advatanges would be uniform deployment and updates.

One solution that came to my mind is to deploy Gentoo Prefix, and install Puppet there with package manager. However, this requires a lot of extra space and some manual patching for each system.

Maybe there are some more elegant and simple solutions?
