I have tested Christian's technique of updating kdevappwizard's copy of ltmain.sh and can now create new C++ projects that build properly. However, a better fix might be for kdevappwizard to get its ltmain.sh (and any other libtool files) from the installed libtool instead of using a copy that can get outdated. kdevelop would then be able to use any libtool updates that were installed.
I have tested Christian's technique of updating kdevappwizard's copy of ltmain.sh and can now create new C++ projects that build properly. However, a better fix might be for kdevappwizard to get its ltmain.sh (and any other libtool files) from the installed libtool instead of using a copy that can get outdated. kdevelop would then be able to use any libtool updates that were installed.