diff --git a/gatchat/ppp_cp.c b/gatchat/ppp_cp.c
index 9ff55233..5e80317f 100644
--- a/gatchat/ppp_cp.c
+++ b/gatchat/ppp_cp.c
@@ -1294,6 +1294,11 @@ void pppcp_set_option_strings(struct pppcp_data *pppcp, const char **opts)
 	pppcp->option_strings = opts;
 }
 
+void pppcp_set_prefix(struct pppcp_data *pppcp, const char *prefix)
+{
+	pppcp->prefix = prefix;
+}
+
 struct pppcp_data *pppcp_new(GAtPPP *ppp, guint16 proto)
 {
 	struct pppcp_data *data;
diff --git a/gatchat/ppp_cp.h b/gatchat/ppp_cp.h
index fb2c89b6..60ea0eff 100644
--- a/gatchat/ppp_cp.h
+++ b/gatchat/ppp_cp.h
@@ -109,6 +109,7 @@ gpointer pppcp_get_data(struct pppcp_data *pppcp);
 GAtPPP *pppcp_get_ppp(struct pppcp_data *pppcp);
 
 void pppcp_set_option_strings(struct pppcp_data *pppcp, const char **opts);
+void pppcp_set_prefix(struct pppcp_data *pppcp, const char *prefix);
 
 void pppcp_add_config_option(struct pppcp_data *data,
 				struct ppp_option *option);
diff --git a/gatchat/ppp_ipcp.c b/gatchat/ppp_ipcp.c
index db414f8a..fc5b33d7 100644
--- a/gatchat/ppp_ipcp.c
+++ b/gatchat/ppp_ipcp.c
@@ -196,7 +196,7 @@ struct pppcp_data *ipcp_new(GAtPPP *ppp)
 	}
 
 	pppcp_set_option_strings(pppcp, ipcp_option_strings);
-	pppcp->prefix = "ipcp";
+	pppcp_set_prefix(pppcp, "ipcp");
 
 	pppcp_set_valid_codes(pppcp, IPCP_SUPPORTED_CODES);
 	pppcp_set_data(pppcp, data);
diff --git a/gatchat/ppp_lcp.c b/gatchat/ppp_lcp.c
index 8580913a..085a9c85 100644
--- a/gatchat/ppp_lcp.c
+++ b/gatchat/ppp_lcp.c
@@ -231,7 +231,7 @@ struct pppcp_data *lcp_new(GAtPPP *ppp)
 	}
 
 	pppcp_set_option_strings(pppcp, lcp_option_strings);
-	pppcp->prefix = "lcp";
+	pppcp_set_prefix(pppcp, "lcp");
 
 	pppcp_set_valid_codes(pppcp, LCP_SUPPORTED_CODES);