Today my company's mail server stop working for a while and the outlook client couldn't receive mails. But my BB can still receive mails. i use the BIS Lite service supported by China Mobile. So, that means BIS can still working when the server down?
This is because incoming mails are routed through Blackberry servers and sent to your BB. It doesn't go through your company mail server. So any disruption in your company mail server will not affect incoming mails to your BB.
The situation will be different if the Blackberry servers are down. Then your Outlook Client will work but your BB will not.