No, 9011 is correct. "011", the international exit code for calling from the US, is what the + gets mapped to in a number such as "+49 xxx". It is followed by the destination country code (which starts with a 3 or 4 for Europe [1]), and then the local number. So for example, to call a number in Germany from a PBX in the US:
9-011-49-(German number) [3]
For long-distance domestic, the national trunk prefix should be used instead. For the US, this is 1 (unrelated to the US country code, which is also 1):
9-1-(10-digit US number)
For local calls, you do not need the trunk prefix, so you would dial:
9-(7-digit US number)
However, no US (or North American) area code nor central office code starts with a 1 [4]. So even in the above two cases, the sequence "911" should never occur.