If your only on a 2G net connection then this is normal for nokias, but if your on a 3/3.5G connection then you should be able to do both at the same time.

Hello biggzy!
Thanks for quick reply!
I am using preferably 2G and with E90 I do not have problems at all.

Regards.

it's because browser cache, not because of data protocols

Threads merged.

same network/operator? either the E90 has two gsm radios, or the network you used your E90 on allows DMT while the one your N900 is on do not.

i sure wish there was a way for the phone to notify the user about this, so one could point to a message or something, rather then a lot of guesswork...

The network operator is same - Mtel in Bulgaria.

When I used to use E90 all my colleagues using Nokias, but no E-series suffered from same problem- even one of them (I think it was Nokia 6600) when you are surfing and call cames the mobile stops his Network Connection ( via PC Suite).
So I think it is was software issue in the past.

For me it can be solved with update, because N900 has very powerfull hardware.
I was told that E90 can make both calls and Internet access because it has a dual core prosessor.

Regards.

Dual core shouldn't matter. It's GPRS itself that limits transmission to either data or phone, not both at the same time. No CPU can fix that, only dual-GSM (two radios) can, as tso said.
EDIT: Update: Not entirely true, see link in tso's post below.

Exactly how the phone behaves (i.e. automatically stall the network connection and accept the call, or reject the call, or whatever, would be a software issue. Maybe the different behaviour you see is down to that.)

except, as i myself was corrected on earlier in the thread, DTM (i incorrectly called it DMT earlier).

http://en.wikipedia.org/wiki/Gprs#Hardware
http://en.wikipedia.org/wiki/Dual_Transfer_Mode

note that this requires the support of the mobile network, as it needs to coordinate that end so that one get an acceptable mix of data and voice traffic.

Thanks for the link, very useful. I wasn't aware of that feature.

nor was i when it was first mentioned. altho i am not surprised at it seems to be fairly recent (2007) feature, and one that seems to be poorly marketed compared to HSPA support (funny that, as GSM/GPRS seems to be highly adaptable to new usage scenarios).