Those two methods uses a "long" for the exponent, but overflow will occur when the exponent is larger than 31 (except for the trivial case where the base is 1).
See also this thread on the dev ML.
Deprecation introduced in revision 1537279.
Methods to be removed before releasing the next major version.
Added changelog entry in r1566074.
This issue was fixed a long time ago.
I think that the issue should be kept open until the method is
Reopening, waiting for the actual deletion of the methods.
Removed methods in commit 745d383af12137ccbcbe1f3cb4c9db73f87a66ca.