Just wanted to add a comment in BRPocock, but I don't have the sufficient privilegies.
So my contribution was for everyone trying to install IBM Integration Toolkit from IBM's Integration Bus bundle.
When you try to run "Installation Manager" command from folder /Integration_Toolkit/IM_Linux (the file to run is "install") you get the error showed in this post.
Further instructions to fix this problem you'll find in this IBM's web page: https://www-304.ibm.com/support/docview.wss?uid=swg21459143
Hope this helps for anybody trying to install that.