public void setHeaderManager(HeaderManager value) {
HeaderManager mgr = getHeaderManager();
if (mgr != null) {
log.warn("Existing HeaderManager '" + mgr.getName() + "' merged with '" + value.getName() + "'");
value = mgr.merge(value, true);
if (log.isDebugEnabled()) {
log.debug("HeaderManager merged: " + value.getName());
for (int i=0; i < value.getHeaders().size(); i++) {
log.debug(" " + value.getHeader(i).getName() + "=" + value.getHeader(i).getValue());
}