diff -ur dovecot-2.2.16/src/plugins/quota/quota.c dovecot-2.2.16-my/src/plugins/quota/quota.c
--- dovecot-2.2.16/src/plugins/quota/quota.c	2015-03-05 17:35:34.000000000 -0500
+++ dovecot-2.2.16-my/src/plugins/quota/quota.c	2015-04-09 15:17:14.000000000 -0400
@@ -1085,7 +1085,7 @@
 
 		/* if size is bigger than any limit, then
 		   it is bigger than the lowest limit */
-		if (size > bytes_limit) {
+		if (bytes_limit > 0 && size > bytes_limit) {
 			*too_large_r = TRUE;
 			break;
 		}
diff -ur dovecot-2.2.16/src/plugins/trash/trash-plugin.c dovecot-2.2.16-my/src/plugins/trash/trash-plugin.c
--- dovecot-2.2.16/src/plugins/trash/trash-plugin.c	2015-01-29 11:01:15.000000000 -0500
+++ dovecot-2.2.16-my/src/plugins/trash/trash-plugin.c	2015-04-13 11:06:44.000000000 -0400
@@ -204,8 +204,16 @@
 		ctx->count_over = 0;
 	}
 
-	ctx->bytes_ceil += size_expunged;
-	ctx->count_ceil += expunged_count;
+        if (ctx->bytes_ceil > ((uint64_t)-1 - size_expunged)) {
+                ctx->bytes_ceil = (uint64_t)-1;
+        } else {
+                ctx->bytes_ceil += size_expunged;
+        }
+        if (ctx->count_ceil < ((uint64_t)-1 - expunged_count)) {
+                ctx->count_ceil = (uint64_t)-1;
+        } else {
+                ctx->count_ceil += expunged_count;
+        }
 	return 1;
 }
 
@@ -214,6 +222,8 @@
 		       uoff_t size, bool *too_large_r)
 {
 	int ret, i;
+	uint64_t size_needed = 0;
+	unsigned int count_needed = 0;
 
 	for (i = 0; ; i++) {
 		ret = trash_next_quota_test_alloc(ctx, size, too_large_r);
@@ -233,9 +243,15 @@
 			break;
 		}
 
+		if (ctx->bytes_ceil!=(uint64_t)-1 && ctx->bytes_ceil < size + ctx->bytes_over) {
+			size_needed = size + ctx->bytes_over - ctx->bytes_ceil;
+		}
+		if (ctx->count_ceil!=(uint64_t)-1 && ctx->count_ceil < 1 + ctx->count_over) {
+			count_needed = 1 + ctx->count_over - ctx->count_ceil;
+		}
+
 		/* not enough space. try deleting some from mailbox. */
-		ret = trash_try_clean_mails(ctx, size + ctx->bytes_over,
-					    1 + ctx->count_over);
+		ret = trash_try_clean_mails(ctx, size_needed, count_needed);
 		if (ret <= 0)
 			return 0;
 	}