This is what's new and changed in the c-ares 1.5.3 release:

 o fix adig sample application compilation failure on some systems
 o fix pkg-config reporting of private libraries needed for static linking
 o fallback to gettimeofday when monotonic clock is unavailable at run-time
 o ares_gethostbyname() fallback from AAA to A records with CNAME present
 o allow --enable-largefile and --disable-largefile configurations
 o configure process no longer needs nor checks size of curl_off_t
 o library will now be built with _REENTRANT symbol defined if needed
 o Improved configure detection of number of arguments for getservbyport_r
 o Improved query-ID randomness
 o Validate that DNS response address matches the request address
 o fix acountry sample application compilation failure on some systems

Thanks go to these friendly people for their efforts and contributions:

 Brad House, Yang Tse, Phil Blundell, Tofu Linden, George Neill
 and obviously Daniel Stenberg

Have fun!