Arduino mini problems

Hello

I've some problems with Arduino mini rev 5 connected to a DS18B20 and Xbee Series 2 Api which transmit temp data to my PC

After uploading my sketch, all work fine. Data are transmitted to the other xbee connected to my PC.

When i unplug the power source, i wait about 5 minutes so i plug the power source (usb) to the arduino mini.

And i then nothing... The arduino seems ton be blocked.

I read this about the Arduino mini :

"The bootloader on Arduinos prior to the Diecimila imposes a 10 second delay after resetting, while it waits for information from the Arduino software. This delay also occurs when the Arduino is powered up, or after programming. There are alternative bootloaders that eliminate these delays, including the Diecimila bootloader, the Adaboot bootloader, the LilyPad bootloader, and others. You can also download the source code and modify the bootloader yourself (see this page for more details and a link to the source). This is useful if you want your project to start up immediately, and especially useful if it receives serial input. If the bootloader receives any input during startup, it will think the Arduino software is trying to talk to it, and delay, possibly indefinitely, starting your program. Here is some info on alternative bootloaders."

Do you think this is my problem ?

I tried to put a delay(11000); on the setup () but this is the same.

Please help me !

I search a solution since many weeks :cry:

Thanks

XBee talks over the D0, D1, yes?
And USB talks over D0, D1 to the PC.
Try removing the Xbee when connected to the PC.