He is most likely bored b/c he is mobile and wants to move, move, move. Exersaucers are restrictive and it is all about walking, climbing, etc. My two kids went through the same and it is an adjustment for you. I had to just shift expectations. No more sitting quietly and playing. Go for walks (with no goal, just enjoy him walking and stopping to look, discover), climb the stairs 50 times, etc. do you have an indoor play center? It is like gymboree on steroids. Where you pay a fee and there are juggle gyms, balls, trampolines, etc. I just saw a quick email from babycenter.com based on age that gave some good ideas for indoor entertainment too.
"Your challenge is to find ways to satisfy her need to mimic the things she sees you do, but safely. Consider getting her a set of plastic keys all her own. You can also give her an old purse of yours and put in a hairbrush and comb, and maybe an old wallet.
There are plenty of other ways to keep your toddler's hands occupied for more than a minute or two. For example, fill a laundry basket with odds and ends, such as plastic containers and lids, paper towel or toilet paper cores, empty cereal boxes (with plastic liners removed), and so on. She'll love getting her hands on — and trying to figure out how to use — objects that look like they have a purpose."
Both my kids would spend hours taking the credit cards out of my wallet (I emptied it of coins so they would not choke) and trying to put them back in (motor skills). And pulling things out of my purse and back in.