libfreetype6 and FT_Seek_Stream / FT_Stream_Seek

[Shaun Jackman <sjackman@telus.net>]

libfreetype6 2.0.9-1 provides FT_Seek_Stream
libfreetype6 2.1.7-2 does not provide FT_Seek_Stream
These two versions of the library are clearly not binary compatible. 
Why didn't the solib version number increase? Why don't we have 
separate packages for the incompatible binary interfaces?

libfreetype6 2.1.7-2 does however provide FT_Stream_Seek. Does anyone 
more familiar with libfreetype know if these two functions are binary 
compatible, outside of their name change?

This issue's been causing me problems for months. Thanks in advance 
for finally putting my tumbled mind to rest.
Shaun