Obliged could be used as verb

- When the power went out, we were obliged to fetch water with a bucket. (to compel or require (someone) to do something, as by circumstance or legality)

- I am obliged to you for your gracious hospitality. (to make indebted or grateful)

- They obliged us by arriving early. (to do a service or favor for)

http://www.thefreedictionary.com/obliged

as a verb it should have been written as:

to be obliged to do something