Question Making Android resolving while on WiFi

[mike.back.access]

This is a long term issue over many versions of Android. multiple email apps, and multiple makers of phones. I guess, I'm just fed up.

On my LAN I have:

• A Public registered domain name
• A Private BIND DNS server with private addresses for that same domain name -- not available to PUBLIC IP lookup.
• Public DNS served by Network Solutions for the domain name.
• A POP3/IMAP mail server
• Public Static IP
• Private IP for local servers
• A firewall port and IP forwarding at router
• Public and private access to mail server
• LAN based wired PC's on LAN CAN connect to the mail server.
• Cellphone is manually set for WiFI connection with local IP and Local DNS.
• There are four separate WiFi APs on the LAN and three different manufactures of the APs. There is NO difference between the APs.
• The phone, while using the LOCAL BIND server, has no problems resolving remote sites.
• IP tools on Cellphone using local BIND via WiFi reports:
  • MX record type for domain name with correct name
  • A record type lookup for FQDM of mail server with correct private IP address
  • Ping via WiFi works from Cell to private IP address
  • Ping via WiFi does NOT works from Cell to FQDN

And so:

• No mail app works with FQDN when connected via WiFi
  • Unless a local IP is listed as the server instead of a FQDN for the server and kills the ability to use when used on cell service.
• Mail app works with FQDN when connected via Cellphone Data service via SIM

Why and how to fix? I need a way to check and control the email on the cell both via WiFi and Cell service.

Is Android simply broken in this way?