NTLM authentication for Axis2/C clients using default http transport is made possible with this package. By default NTLM authentication is disabled in Axis2/C build. to enable NTLM authentication user need to configure Axis2/C with an external NTLM library like Heimdal[1] NTLM support is added to Axis2/C client transport as a dynamically loadedable library called axis2c_ntlm. This library will wrap a external NTLM library like Heimdal to provide NTLM support. Axis2/C is shipped with a wrapper to Heimdal which you can find under heimdal subdirectory here. Developers have tested successfully with a wrapper to libntlm[2] as well. One can write a wrapper to any other external NTLM libary of his choice by implementing axis2_ntlm.h header file and studying the heimdal wrapper here. To enable heimdal NTLM library at build time configure Axis2/C with following option configure --enable-heimdal=yes There are some examples of using NTLM authenticaion with Axis2/C clients under /samples/client/ntlm subdirecory. [1] http://www.h5l.org/ [2] http://josefsson.org/libntlm/