I just tried to renew my prescription for verapamil and got a call from CVS Pharmacy informing me that Aetna will cover the prescription only if filled using the Aetna online pharmacy. They asked if I want to pay the full $42.57 price for it? Well it is blood pressure medication, so yes... I need it.

Aetna did not advise me of this in advance... meanwhile I missed two doses. They are going to get an earful tomorrow.

Through a previous employer, I had Aetna insurance and since at least 2007 they had required all scripts to be filled by their Aetna Rx Home Delivery.  A time to begin reminding drs to write scripts for 90 days only with refills.  You pay the price for two months and get three.

Luckily I never ordered Imitrex, but wondered how a med that's sensitive to a temperature range could sit in my mailbox all day without consequences in the very cold of winter or heat of summer until I got home.

A new 3-month refill can be sent in usually after 2 months, the date is given on the receipt received with the meds.  For instance, with one 90 day script refilled May 23, 2008, the eligible refill date was July 22, 2008.  

An enclosed phone number for Aetna Rx Home Delivery given is 1-866-612-3862.

Also though, if you need a script for only 3 months or less per year, you do not have to go through the mail order, that can be filled at a pharmacy.  If it goes over a three month requirement, mail order only.
If you've gotten the verap script for three months already, the pharmacy cannot fill it using Aetna insurance, it's got to go through Aetna mail order.

Same story as Kevin.

My prior and current job have requirements mandating use of the insurers mail order pharmacy provider. 
At a local pharmacy they will pay a reduced amount the first one or two fills, then require you to fill it through mail order after that. 

Pretty logical really.  Cuts out the middle man for the insurer. 
Refills are simple... I get an email telling me when it is time to refill, then two clicks later it is on the way.