yes - that is normal. The default key for OTR was (rather stupidly) set by us as the 1 key. You can change it to whatever you like by changing the OTR key in features.conf (headers->features.conf). We recommend setting it to a double tap, perhaps ** or *1 or some such. Just be aware that the interdigit delay on features is something like 300ms so you need to press the keys in very quick succession for it to work. You can make the value longer but you'll have to google the parameter (I can't, offhand, remember what it is).
Best
S