whois 12345proxy.pk

Domain:
Turn off cache
Try for webbased whois (don't expect it to work yet)
12345proxy.pk
checking....12345proxy.pk
   $ whois 12345proxy.pk
# WHOIS .PK Domains (PKNIC)

Domain: 12345proxy.pk
Status: Not Registered, and may be available if valid
Available: Yes.