Wei,
I double-checked and I know for sure that I specified the correct account name and password in /etc/pca-proxy.conf on my proxy server. Doesn't pca go to Proxy Server's /etc/pca-proxy.conf to get Sun Online Account info?
The problem you have is on your local pca proxy. Judging from the the output you provided, it's the proxy which fails to download patches. Then pca on the client tries to download the patch, and only succeeds when you provide SOA data to it.
If you have an old version of pca installed as cgi-bin/pca-proxy.cgi, the first thing to try is to update it to the most recent version. Then check /etc/pca-proxy.conf to see if it has the correct login/passwd.
If it still doesn't work, put "debug=1" into pca-proxy.conf, which should write debug output from pca-proxy.cgi to /tmp/pca-proxy-debug.txt - now try to download a patch on the client (e.g. "pca -d 120068-02") and send us the output from /tmp/pca-proxy-debug.txt.
Martin.