Non-leftmost wildcard in DNS record?

Hypothetical situation:

Suppose I ran a hosting firm where I hosted subdomains for people. You could sign up and give me a few bucks a month, and I'd give you yourname.mycompany.com.

Now, say I wanted mail.*.mycompany.com to point to one server and www.*.mycompany.com to point to another.

Is this possible? The RFC seems to think not, Wikipedia seems to think not, but what's stopping a DNS server from having enough logic to return the right thing?

And if so, are there DNS hosting providers that will do this for me so I don't have to run my own DNS?

From stackoverflow

• My solution to this exact problem was to run my own dns, and when a client was added programaticly add the records to the dns, which also allowed me o determine which www server was the least used and apportion the client correctly.

• You could develop your own DNS that uses a non-conforming internal storage mechanism, but you still need to talk the same protocol as the rest of the servers. Also, you usually have to have a non-local backup server that will undoubtedly be unwilling to adopt your DNS server and you'll still have to generate the full names for all of the subscribing companies in the standard format.

• You need to write your own DNS server to support this AFAIK. Nothing stopping you from doing so though. Easy enough to respond to DNS requests however you'd like!

  No hosting company I know of supports wildcarded DNS mid entry.