I know there are tons of threads about wifi issues but I haven't seen this particular problem. If this has already been discussed, please give me the link so I can participate in that discussion.
If I am at home and connected to my wireless router, email will send and receive as expected about 90% of the time. The other 10% of the time would be fantastic to fix but after reading so many threads about this, I fear it is a problem with the stupid phone and is unavoidable...same thing for google talk disconnecting every 5 minutes or when the phone goes to sleep and will not reconnect until I toggle airplane mode or reboot. However, those aren't the issues I'm curious about. I just wanted to post that to make it clear what exactly I'm trying to figure out.
If I have wifi enabled but it isn't connected to a network, my phone will not send or receive anything but phone calls and texts. I was walking around Home Depot and I wanted to send my sister a picture of some baseboards to get her opinion, but the email just wouldn't send. I tried clearing the gmail cache, deleting messages in the outbox and resending, rebooting, etc. Nothing worked until I turned off wifi and it sent immediately. I really hope someone can tell me that is not the intended behavior and there is a way to fix it.
As an aside, this is absolutely ridiculous. Embedded devices should work seamlessly and not require user intervention to make them work by doing things like rebooting, turning on/off features, toggling airplane mode, etc. Imagine if you had to reboot your router or modem this often. No one would tolerate that so I don't know why we tolerate it with a phone.