I've verified with a few hundred BearShare clients. It's easy to reproduce. Connect to a BearShare client and issue a ping. It will only respond with 6346/6348 clients. When you connect to any BearShare client check out the X-Try, 99.999% of the time it only has 6346/6348 clients. My app is operating in ultrapeer mode.

If I connect to limewire, or other hosts, they give all clients, not just 6346/6348 clients.

Handshake from two random bearshares:

GNUTELLA/0.6 200 OK
User-Agent: BearShare 5.2.5.6 (Polska)
X-Try: 41.201.101.6:6346,88.199.180.227:6346,77.253.171.1 1:6348,194.246.107.57:6348,83.27.214.173:6348,85.1 78.144.122:6348,89.228.64.32:6348,89.139.111.69:63 48,24.150.219.250:6346,62.238.207.82:6346
X-Requeries: false
X-Ultrapeer: True
X-Ultrapeer-Needed: True
X-Query-Routing: 0.1
Machine: 1,13,1023,1,1608
Pong-Caching: 0.1
Hops-Flow: 1.0
GGEP: 0.5
Bye-Packet: 0.1
X-Degree: 26
X-Ultrapeer-Query-Routing: 0.1
X-Max-TTL: 4
X-Dynamic-Querying: 0.1
X-Probe-Queries: 0.1
Vendor-Message: 0.1
X-Features: chat/0.1

GNUTELLA/0.6 200 OK
User-Agent: BearShare 5.2.1.9
X-Try: 69.121.82.22:6348,85.221.170.113:6348,85.179.193.1 61:6348,76.179.151.205:6346,81.171.28.169:6346,83. 7.161.41:6348,71.14.99.107:6348
X-Requeries: false
X-Ultrapeer: True
X-Ultrapeer-Needed: True
X-Query-Routing: 0.1
Machine: 1,13,446,1,2405
Pong-Caching: 0.1
Hops-Flow: 1.0
GGEP: 0.5
Bye-Packet: 0.1
X-Degree: 26
X-Ultrapeer-Query-Routing: 0.1
X-Max-TTL: 4
X-Dynamic-Querying: 0.1
X-Probe-Queries: 0.1
Vendor-Message: 0.1