Merge r1775827 from 2.4.x: Merge r1775199, r1775664 from trunk: Fix strict Host: header checking on EBCDIC on zOS, isascii() really means 7 bit ascii, but our strings are in ebcdic for 99.95% of the lifetime of the server. remove initial isascii check entirely We are already checking an even narrower set of characters just below. Submitted by: covener Reviewed/backported by: jim