Here’s what I did to get my Yahoo Mail importing into Mail.app with the latest Yahoo.lua 0.1.9d for FreePOPS (or MacFreePOPS).
I opened yahoo.lua and changed line 252 from:
strRegExpWebSrvUrl = “webserviceURL: ‘([^’]+)'”,
strRegExpWebSrvUrl = “webservice: ‘([^’]+)'”,
Then I downloaded Firefox 22.214.171.124, switched on the Yahoo Mail Beta, and then turned it back off.
Next, I quit my mail client and quit FreePops (in my case, MacFreePOPS).
Finally, I launched MacFreePops and then fired up my mail client, Mail.app again. Everything started downloading like the old days!!!