diff --git a/parseany.go b/parseany.go
index 0407b79..b427d68 100644
--- a/parseany.go
+++ b/parseany.go
@@ -1345,7 +1345,12 @@ iterRunes:
 				//     15:44:11 UTC+0100 2015
 				switch r {
 				case '+', '-':
-					p.tzlen = i - p.tzi
+					if datestr[p.tzi:i] == "GMT" {
+						p.tzi = 0
+						p.tzlen = 0
+					} else {
+						p.tzlen = i - p.tzi
+					}
 					if p.tzlen == 4 {
 						p.set(p.tzi, " MST")
 					} else if p.tzlen == 3 {
@@ -1679,10 +1684,13 @@ iterRunes:
 			p.trimExtra()
 		case timeWsAlphaZoneOffset:
 			// 06:20:00 UTC-05
-			if i-p.offseti < 4 {
+			switch i - p.offseti {
+			case 2, 3, 4:
 				p.set(p.offseti, "-07")
-			} else {
+			case 5:
 				p.set(p.offseti, "-0700")
+			case 6:
+				p.set(p.offseti, "-07:00")
 			}
 
 		case timePeriod:
diff --git a/parseany_test.go b/parseany_test.go
index aeb201f..0193b52 100644
--- a/parseany_test.go
+++ b/parseany_test.go
@@ -419,6 +419,7 @@ var testInputs = []dateTest{
 
 	{in: "Wed,  8 Feb 2023 19:00:46 +1100 (AEDT)", out: "2023-02-08 08:00:46 +0000 UTC"},
 	{in: "FRI, 16 AUG 2013  9:39:51 +1000", out: "2013-08-15 23:39:51 +0000 UTC"},
+	{in: "Mon, 1 Dec 2008 14:48:22 GMT-07:00", out: "2008-12-01 21:48:22 +0000 UTC"},
 }
 
 func TestParse(t *testing.T) {