I am not sure what you mean. My DNS server is the ns26a.sbc-webhosting.com, ns26b.sbc-webhosting.com servers provided by my ISP (see below). If I understand you then DNS only knows of 71.158.190.150 so how does zimbra know that internal lan address 172.16.1.38 should use the static ip 71.158.190.150 assigned to my lan router???
I guess I don't understand some basic principle, can you explain???
kumasi.net. IN MX 25 mail.kumasi.net.
mail.kumasi.net. IN A 71.158.190.150
smtp.kumasi.net. IN A 71.158.190.150
kumasi.net. IN A 71.158.190.150
kumasi.net. IN A 71.158.190.150
www.kumasi.net. IN A 71.158.190.150
kumasi.net. 86400 IN NS ns26a.sbc-webhosting.com.
kumasi.net. 86400 IN NS ns26b.sbc-webhosting.com.
www.kumasi.net. 86400 IN MX 50 mail-fwd.sbc-webhosting.com.
webmail.kumasi.net. 86400 IN A